How do you solve number #4?
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Answer:
b
Step-by-step explanation:
Area of the shaded region =[ (3x-2)(x+3) ] - [ x*6 ]
= 3x*x +3x*3 + (-2)*x + (-2)*3 - 6x
=3x² + 9x - 2x - 6 - 6x {bring like term together}
=3x² + 9x - 2x - 6x - 6
= 3x² + x - 6 {9x - 2x - 6x = 9x - 8x = x}
Area = 24 square units
3x² + x - 6 = 24
3x² + x - 6 - 24 = 0
3x² + x - 30 = 0
Product = 3* -30 = -90
Sum = 1
Factors = 10 , (-1)
3x² + x - 30 = 0
3x² - 9x + 10x - 10*3 = 0
3x*(x - 3) +10*(x - 3) = 0
(x-3)(3x +10) = 0
3x + 10 is ignored because measurements will not be in negative values.
x - 3 = 0
x = 3