Answer:
The height is 5 and the base is 9
Explanation:
The area of a parallelogram is given by
A = bh
45 =x(x+4)
Distribute
45 =x^2+4x
Subtract 45 from each side
45-45 =x^2 +4x-45
0 = x^2 +4x-45
Factor
What two numbers multiply to -45 and add to 4
9+-5 = -45
9-5 =4
0=(x+9) (x-5)
Using the zero product property
0= x+9 0 = x-5
x=-9 x=5
Since length cannot be negative
x=5 is the solution
x=5
x+4 = 5+4 =9