Answer:

Step-by-step explanation:
4x^2+ 12x = 135
D=b²−4ac=122−4(4)(−135)=144+2160=2304=48²

I believe the answer is 9
Answer:
both choices with 2x+y = -3
Step-by-step explanation:
to have the solution (-4, 5), that point must be on both equations/functions, meaning it must be on either one.
in other words, if the point is not on at least one of the functions, it cannot be a solution for that system.
the given function
2x + y = -3
looks like for the point (-4, 5)
2×-4 + 5 = -3
-8 + 5 = -3
-3 = -3
correct.
but
-2x + y = -3
looks like for (-4, 5)
-2×-4 + 5 = -3
8 + 5 = -3
13 = -3
wrong. the point is not on this function.
as we can therefore rule out 2 of the answer options, the other 2 most be correct.
Answer:
6+3.4=9.4
Step-by-step explanation:
the 6 and the 3 add normally, and you just add 0.4 in the decimal place