Answer: 70cm³
EXPLANATION:
1/2 x base x height x 2 (this is to find the surface area of one of the triangular faces since the other side of the triangular shape has the same measurements you should multiply it by 2 straight away since it makes it easier for you)
1/2 x base x height x 2
1/2 x 3 x 3 x 2 ← <em>(to get the height of the triangle substract 7 from 10)</em>
1/2 x 18 ←<em> (multiply 3x3x2=18) </em>
9cm³ ←<em>(since 18 is 2x9 your answer is 9cm³)</em>
<em></em>
1/2 x base x height x 2 (this is to find the surface area of the other triangular face with different measurements and since the other side of the triangular shape has the same measurements you should multiply it by 2 straight away since it makes it easier for you)
1/2 x base x height x 2
1/2 x 4 x 3 x 2 ← <em>(to get the height of the triangle substract 7 from 10)</em>
1/2 x 24 ←<em> (multiply 4x3x2=24) </em>
12cm³ ←<em>(since 24 is 2x12 so your answer is 12cm³)</em>
<em></em>
Then next you have to find the surface area of one face of the rectangle and multiply it by 2 since the back side of the rectangle has the exact same measurements. The formula to find the area of a rectangle is area= length x breath
A= 3x7= 21cm³
then find the area of the other rectangular face with different measurements and multiply it by 2 since the back side of the rectangle has the exact same measurements. The formula to find the area of a rectangle is area= length x breath
A= 4x7= 28cm³
<u>FINALLY</u>
add all the areas of the faces you have found and you'll get the total surface area!
<u>9+12+21+28=70cm³</u>
Thank you! I hope you understood something and I hope you have a great day! good luck!
