x = number
When 30 times a number is increased by 32 ,the result is equal to twice the square of the number means:
30 x + 32 = 2 x²
Subtract 2 x² to both sides
- 2 x² + 30 x + 32 = 0
Divide both sides by - 2
x² - 15 x - 16 = 0
The solutions are:
x = - 1
and
x = 16
Check of results:
30 x + 32 = 2 x²
30 ∙ ( - 1 ) + 32 = 2 ∙ ( - 1 )²
-30 + 32 = 2 ∙ 1
2 = 2
30 ∙ 16 + 32 = 2 ∙ 16²
480 + 32 = 2 ∙ 256
512 = 512
When 30 times a number is increased by 32 ,the result is equal to twice the square of the number. Find the number
3 answers
512
The number is 16.