Find and explain the error in the work below.
Multiply: (-4m+2)(2m+5)
-4m(2m)+4m(5)+2(2m)+2(5)
-8m^2+20m+4m+10
-8m^2+24m+10
Find and explain the error the work for the given problem.
The error in the work is in the signs while applying the distributive property.
When multiplying -4m(2m), the correct answer is -8m^2 as shown in the work. However, when multiplying -4m(5), it should be -4m * 5 = -20m, not +20m as shown. The rest of the calculations are correct.
So the correct work should be:
(-4m+2)(2m+5)
-4m(2m) - 4m(5) + 2(2m) + 2(5)
-8m^2 -20m + 4m + 10
-8m^2 -16m + 10