
Here we have two fractions top and bottom
divide by

We have division in between . we reverse the second fraction and multiply it with first fraction.
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Now we factor both numerator and denominator
4x^2+12x-16 = 4 (x+4)(x-1)
2x+10 = 2(x+5)
x^2+9x+20 = (x+5)(x+4)
6x+24 = 6(x+4)
Replace the factors,
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We cancel out same factors at the top and bottom
So it becomes ,
