The expression 2(a + b) = -8.1 for certain value of a and b. Find the value of the following expression for the same value of a and b: 3(a+b)

-12.15

Step-by-step explanation:

2(a+b)=-8.1

a+b=-4.05

3(a+b)=3(-4.05)

3(a+b)=-12.15

x² + 3x + 7 = 0       [ax² + bx + c]

a = 1

b = 3

c = 7

quadratic formula:

    (+/- is this ±)

plug in the numbers into the variables

your answer is a