Use the formula:

B refers to the base and H refers to the height of the triangle.
As such, multiply both the base and height of the triangle and divide the answer by 2, to find the area of the triangle.
Answer: x = 39 because 39 + 102 = 141 and 180 - 141 = 39
the answer would be -8<x<2
Answer:
F' corresponds to point F
Step-by-step explanation:
When a point is the result of some transformation, we often designate that result using the base name of the original, with a prime (') added. In this case, we expect that F' is the transformation of point F.
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<em>Comment on point naming</em>
Of course, points can be given any name you like. These conventions are adopted to aid in communication about transformations and correspondence between points. It would be unusual--even confusing, but not unreasonable, for point F' to correspond to point D, for example. In the case of certain transformations, point F' may actually <em>be</em> point D.