Showing posts with label Quadratic Equations. Show all posts
Showing posts with label Quadratic Equations. Show all posts

Friday, May 17, 2013

10th Grade Math Sample Tests

Introduction to mathematics:

Mathematics is the study of quantity, structure, space, and change. Mathematicians seek out patterns, formulate new conjectures, and establish truth by rigorous deduction from appropriately chosen axioms and definitions. There is debate over whether mathematical objects such as numbers and points exist naturally or are human creations. (Source: Wikipedia)

Topics under 10th grade math:

Linear and non linear equations
Quadratic equations
Standard form of line equations
Slope intercept form
Trigonometry
Geometrical areas and volume
Here, we see about linear equations, quadratic equations, and trigonometry.

Please express your views of this topic system of linear equations examples by commenting on blog.

Example problems for 10th grade math sample tests


10th grade math sample test example problem 1:

Solve the linear equations 2x - 3y = 6 and x + 2y = 10

Solution:

The given linear equations are 2x - 3y = 6 and x + 2y = 10

2x - 3y = 6 ------- (equation 1)

x + 2y = 10 ------- (equation 2)

Multiply the equation 1 by 2, we get

4x - 6y = 12 ------ (equation 3)

Multiply the equation 2 by 3, we get

3x + 6y = 30 ------- (equation 4)

Add the equation 3 and equation 4, we get

7x = 42

Divide by 7 on both the sides, we get

x = 6

Substitute the value of x in the first equation, we get

18 + 6y = 30

Subtracting the above equation by 18 on both the sides, we get

6y = 12

Divide by 6 on both the sides, we get

y = 2

Answer:

The final answer is x = 6, y = 2

10th grade math sample test example problem 2:

Solve the linear equation 3x - y = 24, x = 3y using substitution method.

Solution:

Given equations are 3x - y = 24 and x = 3y

3x - y = 24 ---------- (1)

x = 3y ---------- (2)

Substitute the equation 2 in equation 1, we get

9y - y = 24

8y = 24

Divide the above equation by 8 on both the sides, we get

y = 3

Substitute the value of y in equation 2, we get

x = 3 (3)

x = 9

Answer:

The final answer is x = 9, y = 3.

10th grade math sample test example problem 3:

Find the value of (sin 30° + cos 45°)

Solution:

Given (sin 30° + cos 45°)

We know that,

sin 30° = 0.5

cos 45° = 0.707

Substitute the above values in the given, we get

(sin 30° + cos 45°) = 0.5 + 0.707

= 1.207

Answer:

The final answer is 1.207

Understanding Trig Integral Table is always challenging for me but thanks to all math help websites to help me out.

Practice problems for 10th grade math sample tests


10th grade math sample test practice problem 1:

Solve the linear equations 5x + y = 36 and x - 3y = 4

Answer:

The final answer is x = 7, y = 1.

10th grade math sample test practice problem 2:

factorize the given quadratic equation x2 - 13x + 22 = 0

Answer:

The final answer is x = 11 and x = 2

10th grade math sample test practice problem 3:

Find the value of (cos 60° + tan 45° + sin 90°)

Answer:

The final answer is 2.5

Tuesday, March 19, 2013

Quadratic Equations with Square Roots

Introduction :

In mathematics, a quadratic equation is one of a polynomial equation of the second degree. The general form is

ax^2+bx+c=0

Where x represent a variable, and a, b, and c, are the constants, with a ? 0. (If a = 0, the equation becomes a linear equation.). The constants a, b, and c, are called, the quadratic coefficient, the linear coefficient and the constant term or free term. The word "quadratic" comes from quadratus; it is the Latin word for "square." Quadratic equations can also be solved by factoring, completing the square, graphing, Newton's method, and using the quadratic formula.

Source: wikipedia


Example problems on Quadratic equations with square roots:

Example 1:

Determine all real solutions to the equation

Sqrt (x + 1) = 4

Solution:

Given equation is
sqrt (x + 1) = 4

Squaring on both sides, then the above equation becomes
[sqrt (x + 1)]^2 = 4^2

Simplify the above equation
x + 1 = 16

Solve for x.
x = 15

NOTE: Because we squared both sides not including putting any conditions, extraneous solutions may be introduced, checking the solutions is necessary.

Check the left side (LS) of the given equation when x = 15

LS = sqrt (x + 1) = sqrt (15 + 1) = 4

Check the right Side (RS) of the given equation when x = 15

RS = 4

When x = 15, the left and the right sides of the given equation are equal: x = 15 is a solution to the given equation.

Example 2:

Determine all real solutions of the equation

Sqrt (3 x + 1) = x - 3

Solution:

Given equation is
sqrt ( 3 x + 1) = x - 3

Squaring on both sides, then the above equation becomes
[sqrt ( 3 x + 1) ]^2 = (x - 3)^2

Simplify the above equation
3 x + 1 = x^2 - 6 x + 9

Rewrite the above equation in factor form.
x^2 - 9 x + 8 = 0

The above form is a quadratic equation with 2 solutions
x = 8 and x = 1


Practice problems on quadratic equations with square roots:


1) Determine the real value of the given quadratic equation with square roots.

Sqrt (2 x + 15) = 5
Answer: x = 5

2) Determine the real value of the given quadratic equation with square roots.

Sqrt (4 x - 3) = x – 2

Answer: x = 7

Monday, October 15, 2012

Solving Quadratic Equations

Introduction :

An equation in the form of ax2 + bx + c = 0, where a, b, c ? R and a ?0 is called a quadratic equation. It is an equation with degree 2. For example, 5x2 + 6x + 7 = 0, 9x2 – 4 = 0, 2x2 – 3x =0 are quadratic equations. If p(x) = 0 is a quadratic equations, then the zero of the polynomial  p(x) are called the roots of equation p(x) = 0. Find the roots of a quadratic equation is called as solve the quadratic equations.

Solution of Quadratic Equations Example

To solve quadratic equation by using factorization method using at what time the quadratic equation is expressible as the product of two linear equations. Quadratic equation of the form ax2+bx+c=0 here a,b,c,d are called constants can be used to reduced the form of a quadratic equations.

Example 1:

Solving quadratic equations X2+9x-10

Solution:

Step 1:

List out the factors

1x-10, -1x10

Step 2:

Find the factor the sum value is 9

-1+10=9

Step 3:

Check using distributive property

(X-1)(x+10)=x2+10x-x-10

X2+9x-10

Step 4: back to original equation

X2+9x-10 we get two values for x.

X-1=0=>x=1

x+10=0=>x=-10

Answer:  x=1, x=-10

Example 2:

Solving the quadratic equations 2x2 + 3x – 5 = 0

Solution: 2x2 + 3x – 5 = 2x2 + 5x – 2x – 5

= x (2x + 5) – 1(2x + 5)

= (x – 1) (2x + 5)

Since 2x2 + 3x – 5 = 0 we get (x – 1) (2x + 5) = 0

=>x – 1 = 0 or 2x + 5 = 0

=>x = 1, –5/2

The solution set = 1, -5/2

Example 3:

Solving the quadratic equations 64x2 – 36 = 0

Solution: 64x2 – 36 = 0 or (8x + 6) (8x – 6) = 0

Or x = –6/8 = –3/4

Or x = 6/8 = 3/4

The solution set =-3/4, 3 /4

Example 4:

Solving the quadratic equations 3x2 – 4x = 0

Solution: 3x2 – 4x = x (3x – 4)

Since 3x2 – 4x = 0, we get x (3x – 4) = 0

Or x = 0

Or 3 x –4 = 0

=> 3x = 4

=> x = 4/3

Quadratic Equation Practice Problem

1) Solving the quadratic equations x2+4x-5=0

Answer:

X=1, x=-5

2) Solving the quadratic equations x2-5x-6

Answer:

x=-1, x=6