A triangle has sides of 4,7, and 10. in another triangle shortest side is 12 and the longest side is x. Write a proportion that models the situation. And solve for x.

Phrase "Write a proportion that models the situation." means triangles are similar and corresponding sides are proportional.

12 x

---- = -----

4 10

after cross-multiplication we have:

4x = 12 * 10

x = 120 / 4

==========

12 x

---- = -----

4 10

after cross-multiplication we have:

4x = 12 * 10

x = 120 / 4

*x = 30 (units)*==========

*For this particular case, could be good practice, first, to simplify the fraction on the left side of proportion:**3 x**--- = ----**1 10**1*x = 3*10**x = 30*