Answer:
Dimensions are 12 , 5
Step-by-step explanation:
Area of rectangular mural = length * width
length * width = 60 square feet
(x + 10)(x + 3) = 60
Use FOIL method
x*x + x*3 + 10*x + 10*3 = 60
x² + <u>3x + 10x</u> + 30 = 60 {Combine like terms}
x² +<u> 13x</u> + 30 - 60 = 0
x² + 13x - 30 = 0
Sum = 13
Product = -30
Factors = 15 , -2 (15+ (-2) = 13 ; 15*(-2) = -30)
x² + 15x - 2x - 30 =0 {Rewrite middle terms}
x(x + 15) - 2(x + 15) = 0
(x + 15)(x - 2) =0
x - 2 = 0 {Ignore (x +15) as dimensions wont have a negative value}
x = 2
x + 10 = 2 + 10 = 12
x + 3 = 2 + 3 = 5
Dimensions are 12 , 5
