Answer:
20
Step-by-step explanation:
20 percent of 40 is 5
so 20 is d answer
To effectively determine the correct answer, it would be helpful to write this into an algebraic expression. We let x as the number. We do as follows:
<span>Four times the square of a certain number increased by 6 times the number equals 108.
4x^2 + 6x = 108
The numbers can be either of the following since the equation generated was a quadratic equation which has two roots.
x = 4.5
x = -6 </span>
Y = 2x - 3 . . . (1)
y = -2x + 5 . . . (2)
Equating (1) and (2),
2x - 3 = -2x + 5
2x + 2x = 5 + 3
4x = 8
x = 8/4 = 2
x = 2
y = 2(2) - 3 = 4 - 3 = 1
y = 1
Solution = (2, 1)