hello, could you please explain this to me?
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Find the value of r(q(4)), so first you need to find the value of q(4).
q(4), this means that x = 4, so substitute/plug it into the equation to find the value of q(x) when x = 4:
q(x) = -2x - 1 Plug in 4 into "x" since x = 4
q(4) = -2(4) - 1
q(4) = -8 - 1
q(4) = -9
Now that you know the value of q(4), you can find the value of r(x) when x = q(4)
r(x) = 2x² + 1
r(q(4)) = 2(q(4))² + 1 Plug in -9 into "q(4)" since q(4) = -9
r(q(4)) = 2(-9)² + 1
r(q(4)) = 2(81) + 1
r(q(4)) = 163 163 is the value of r(q(4))