Answer: 6
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Work Shown:
AC/QS = BC/RS
4/10 = m/15
4*15 = 10*m
60 = 10m
10m = 60
m = 60/10
m = 6
The first equation is possible because the triangles are similar. The horizontal sides AC and QS form the ratio AC/QS. This is equal to the ratio of the diagonal sides BC/RS since similar triangles have their sides in proportion.
After the equation is set up, we cross multiply and then solve for m.
