A.) multiply these numbers the quickest and easiest way possible: 87 x 5 x 2 b.) explain how you were able to quickly determine the product. justify your reasoning using a property of multiplication.

It is easy to multiply numbers by 10: you simply have to add an extra zero at the end.

This means that, using associative property, we know that

87 x 5 x 2=(87 x 5) x 2=87 x (5 x 2)

The last expression is the easiest to compute, because we have

87 x (5 x 2) = 87 x 10 = 870

Hope I helped.

answer: 60

step-by-step explanation:

1/2a + (2/3×30)   = 50

1/2a + 20 = 50

1/2a = 30

a = 60

geometry: triangles

solvers

lessons

answers archive

call the larger triangle abc

then the smaller triangle cde is similar to abc (all angles are equal, aaa).  

ab is the side that is 36, and we wish to find de, the side corresponding to ab

area_cde = area_abc - area_cde --> area_abc / area_cde = 2

let x=length of de

ratio of areas = (ratio of sides)^2

+2+=+%2836%2fx%29%5e2+

+2+=+1296%2fx%5e2+

++x%5e2+=+1296%2f2+=+648+

25.45584