I need help with algebra

x³ + 3x² - 5

Step-by-step explanation:

(x³ - 5x + 4) + (2x² + 5x - 6) - (-x² + 3)

x³ - 5x + 4 + 2x² + 5x - 6 + x² - 3

x³ + 3x² - 5

We are given [ H(x) = A(x) + B(x) - C(x) ]. Substitute with the given functions.

H(x) = (x³ - 5x + 4) + (2x² + 5x - 6) - (-x² + 3)

~Simplify

H(x) = (x³ - 5x + 4) + (2x² + 5x - 6) + (x² - 3)

~Combine like terms

H(x) = x³ + (2x² + x²) + (-5x + 5x) + (4 - 6 - 3)

~Simplify

H(x) = x³ + 3x² - 5

The answer is x³ + 3x² - 5

Best of Luck!

d

step-by-step explanation:

we have three similar triangles, because each has a right angle and shares an angle.   let's write the angles in order: opposite to short leg, long leg, hypotenuse.

cab similar to bad similar to cbd

or as ratios,

ca: ab: cb = ba: ad: bd = cb: bd: cd

we also know

ac = ad + cd

(ad+cd): ab: cb = ba: ad: bd = cb: bd: cd

(ad+cd)/cb=cb/cd

we have cb=6, ad=5 and seek x=cd.

we reject the negative root and conclude x=4

answer: 4