Find the missing parts of the triangle. Round to the nearest tenth when necessary or to the nearest minute as appropriate. a = 7.3 in.
b = 13.2 in.
c = 15.8 in.

A = 27.3°, B = 56.1°, C = 96.6°
No triangle satisfies the given conditions.
A = 29.3°, B = 54.1°, C = 96.6°
A = 25.3°, B = 56.1°, C = 98.6°

Use the Law of Cosines to find the measure of angle A from the lengths of the sides.

A = arccos[(b²+c²-a²)/(2bc)] ≅ 29.9°

B = arccos[(a²+c²-b²)/(2ac)] ≅ 54.8°

C = 180 - A - B = 95.3°

starting with:    

5 + x - 12 = 2x - 7   

5 + x - 12 - x = 2x - 7 - x (subtract x from both sides)   

5 - 12 = x - 7 (combine and cancel x's from both sides)   

5 - 12 + 7 = x - 7 + 7 (add 7 to both sides)   

0 = x (add numbers together on both sides)       

so in order for the equation to be true, x must be 0.   

trying x = -0.5   

5 + x - 12 = 2x - 7 (original equation)   

5 + -0.5 - 12 = 2(-0.5) - 7 (plug in value of x)   

5 + -0.5 - 12 = -1 - 7 (did multiplication)   

-7.5 = -8 (did addition on both sides)       

since -7.5 is obviously not equal to -8, the value of -0.5 for x is wrong.   

trying x = 0   

5 + x - 12 = 2x - 7 (original equation)   

5 + 0 - 12 = 2(0) - 7 (plug in value of x)   

5 + 0 - 12 = 0 - 7 (did multiplication)   

-7 = -7 (did addition on both sides)       

since -7 equals -7, that demonstrates that the value of 0 for x is correct.   

trying x = 1   

5 + x - 12 = 2x - 7 (original equation)   

5 + 1 - 12 = 2(1) - 7 (plug in value of x)   

5 + 1 - 12 = 2 - 7 (did multiplication)   

-6 = -5 (did addition on both sides)       

since -6 is obviously not equal to -5, the value of 1 for x is wrong.

too hard the other guy did it

step-by-step explanation: