Question

a) 3(2x²-12)=5x²


b) 2x²+5=55

Answer 1

A) 3(2x²-12)=5x²
6x² - 36 = 5x²
6x² - 5x² = + 36
1x² = 36
x² = 36/1

x² = 36

x = + - √36      ( √36 = 6)
x = + - 6

x' = - 6
x" = + 6

 

b) 2x²+5=55

2x² + 5 = 55
2x² = 55 - 5
2x² = 50
x² = 50/2
x² = 25

x = + - √25       (√25 = 5)


x' = - 5
x" = + 5

Answer 2

a) 3(2x²-12)=5x²

6x² - 36 = 5x²
6x² - 5x² = 36
x² = 36
x = √36
x = +/- 6

R.: x = + 6 e x = - 6
______________________________

b)
2x² + 5 = 55
2x² = 55 - 5
2x² = 50
x² = 50/2
x² = 25
x = √25
x = +/- 5

R.: x = + 5 e x = - 5