gr10 math
posted by Rebecca on .
The length of a rectangle is 2cm more than the width. The area is 24cm^2. What are the dimensions of the rectangle?
Let x be the width.
Let x +2 be the the length.
A = lw
24cm^2 = (x+2)x
24cm^2= x^2 + 2x
24cm^2 + x^2 = 2x
25cm^2 = 2x
25cm^2 /2 = 2x /2
12.5cm^2 = x
l = x + 2
l = 12.5 cm^2 + 2
l = 14.5 cm^2
Therefore the dimensions of the rectangle are 12.5cm^2 and 14.5cm^2.
did i do this question right?

x^2 + 2x = 24
x^2 +2x 24 = 0
Find two factors of 24 that will sum to give the value of the middle term, 2.
(x+6)(x4) = 0
x = 6 or 4
Since width cannot be a negative number, x = 4, then length = 4 + 2 = 6