Find b and c so that the parábola y=-3x^2 +bx+c has x-intercepts 1 and -4

so b=-9 while c=12.

Step-by-step explanation:

If you have x-intercepts 1 and -4, then that means f(1)=0 and f(-4)=0.

You are given

So you have the system of equations to solve:

Evaluating the exponents:

Doing a little bit of multiplying:

Let's add 3 on both sides of equation 1 and 48 on both sides of equation 2:

Subtracting the equations will eliminate c.

Let's do that:

Divide both sides by 5:

Simplify:

If b=-9 and b+c=3 then -9+c=3 implies c=9+3=12.

so b=-9 while c=12.

$15 each

step-by-step explanation:

$45/3 children= $15 each