Answer:
(x+1.5)^2 -10.25
Step-by-step explanation:
1)first, we half 3 to give us 1.5
(x+1.5)^2
2)square 1.5=2.25
so far we have (x+1.5)^2 - 2.25 --- the negative sign from 2.25 is part of the formula
3)we subtract 8 from -2.25. the 8 comes from here shown in bold ----- x^2+3x-8
4) (x+1.5)^2 -2.25 - 8
5)simplify the last part by doing -2.25 - 8= -10.25
6)answer is (x+1.5)^2 - 10.25