The sides of an rectangle was 5cm by 9cm. When both dimension were increased by an equal amounts the area of the rectangle increased by 120 cm^2 find the dimensions of the new rectangle.

5 answers

New rectangle has area of
(9+x)(5+x)

so ...

(9+x)(5+x) - 45 = 120
x^2 + 14x - 120 = 0
(x + 20)(x-6) = 0
x = -20 (silly) or x = 6

new rectangel is 11 by 15

check:
new rect. = 11x15 = 165
old rect. = 5x9 = 45

increase = 165-45 = 120 Checks!
What is 7/12 as a percent and decimal???
Divide 7 by 12 to get the decimal.
7/12=0.5833 (3 repeating)
Multiply by 100 to get percent.
58.33% (3 repeating)
Thank You Kathleen your a life saver
suppose that the height of an object shot straight up is given by
h=544t -16t^2. h= feet and t= seconds
Find the maximum height and the time at which the object hits the ground