M∠A′B′C′ = m∠ABC would be the answer for this. if you could give me a pic, I could answer. I don't see Triangle ABC
<h3>The base area of triangular prism container is 42.8 cubic centimeter</h3>
<em><u>Solution:</u></em>
<em><u>The volume of triangular prism is given as:</u></em>

Given that,
A triangular prism container is full of water of 428 cubic cm
The water is 10 cm deep
Therefore,
v = 428 cubic cm
h = 10 cm
<em><u>Substituting the values we get,</u></em>

Thus the base area of triangular prism container is 42.8 cubic centimeter
You would multiply both 2x and -8 by 5. The answer would be 10x-40.