Answer:
a² + 16a - 612 = 0
Explanation:
Here is the complete question :
The width of an extra large rectangle poster is 8 inches more than half its length. The area of this poster is 306 square inches
Write an equation in one variable that could be used to find the number of inches in the dimensions of this poster.
Area of a rectangle = length x width
Let length = a
width = 8 + 1/2a
Area = (8 + 1/2a) x a
306 = (8 + 1/2a) x a
multiply both sides of the equation by 2
612 = 16a + a²
a² + 16a - 612 = 0
the dimensions of the poster can be determined using quadratic formula