You do the sum(40) subtracted by 8, the answer from that divided by 2 since Erin's two times younger.
40-8=32
32÷2=16
Then if you want to check it you do the opposite and get the same sum(40) so 16×2=32 and 32+8=40
7 goes in to 30 four times i believe :)
<h3>
Answer: 1.8</h3>
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Work Shown:
Use the tangent ratio
tan(angle) = opposite/adjacent
tan(B) = AC/AB
tan(61) = AC/1
tan(61) = AC
AC = tan(61)
AC = 1.80404775527142
AC = 1.8
The river is about 1.8 miles wide between points A and C.
Make sure your calculator is in degree mode. One way to check is to type in tan(45) and you should get 1.
Please find the attached photograph for your answer
