Question

Please helpppppp! I really don't understand

Answer 1

AB=8.1 and B=29.6

Explanation:

1) To find the measure of AB, use the law of cosines

`c^2=4^2+7^2-2(4)(7)cos(90)`

`c^2 = 16+49 -56cos(90)\\c^2= 65\\c=8.1`

2) Use law of sines to find the measure of B

`(8.1)/(sin(90)) =(4)/(sin(B))`

B=29.6