Solving EquationsSolving Equations

A linear or First degree A linear or First degree EquationEquation

• Eg. 2y+1 = 13Eg. 2y+1 = 13

1.Solving linear equations 1.Solving linear equations by using inverse operationsby using inverse operations

x – 7 = -3x – 7 = -3 + 7 = +7 (adding 7 on each side)+ 7 = +7 (adding 7 on each side) ---------------------------- X = 4X = 4

3x = 213x = 21

3x / 3 = 21 /3 ( dividing each by 3)3x / 3 = 21 /3 ( dividing each by 3) X = 7X = 7

Solving Equations with Solving Equations with parenthesesparentheses

Solve 3(b+2) +2b = 21Solve 3(b+2) +2b = 21

3(b+2) +2b = 213(b+2) +2b = 21

3b+6 +2b = 213b+6 +2b = 21 5b+6 = 215b+6 = 21 5b+6-6 = 21-65b+6-6 = 21-6 5b = 155b = 15 5b/5 = 15/ 55b/5 = 15/ 5 Therefore b = 3Therefore b = 3

Solving equation contains fractions

m/3 – m/4 = 2

m/3 – m/4 = 2

• 12(m/3) – 12(m/4) = 12(2) [ L.C.M. of 3 &4 is 12)

• 4m – 3m = 24• So, m= 24

Solving Equations by cross multiplying

If x / 3 = (x + 4)/5 , what is the value of x?

If x / 3 = (x + 4)/5 , what is the value of x?

5(x) = 3(x+4)

5x = 3x +12

2x = 12

x = 12 / 2

Therefore x= 6

Using A root of an equation to Using A root of an equation to answer a questionanswer a question

If 3y – 2 = 4 , what is the value If 3y – 2 = 4 , what is the value of y – 2 ?of y – 2 ?

If 3y – 2 = 4 , what is the value of If 3y – 2 = 4 , what is the value of y – 2 ?y – 2 ?

If 3y – 2 = 4 ,then 3y = 6 If 3y – 2 = 4 ,then 3y = 6 Therefore y = 2Therefore y = 2 The value of y-2 = 2 – 2 = 0The value of y-2 = 2 – 2 = 0

The ENDThe END