I need help! It's all in the picture, please show work and no violating rules of

860cm²

Step-by-step explanation:

1. area of the side triangle:

(15×8)×2= 120×2= 240cm²

there's two side triangles with the same length and width, so just multiply by two.

2. area of the square on top:

20×8= 160cm²

3. area of the rectangle behind:

20×8= 160cm²

4. area of the square below:

20×15= 300cm²

5. the total of all areas (surface area):

240+160+160+300= 860cm²

c.   x=2.4cm

step-by-step explanation:

similar triangles are triangles which have the same shape but not the same size. this means their angle measures are equal but their side lengths are not instead they are proportional. to solve, we will set up a proportion and solve.

a proportion is two equal ratios set equal to each other. we form the ratios by finding corresponding sides (sides which match to each other on both triangles by their position). out ratios will be one side of the small triangle over the corresponding side on the big triangle as shown below:

.

to solve the proportion, we'll cross multiply by multiplying numerator with denominator across the equal sign.

v = 1/3 a^2h

step-by-step explanation:

the volume is 1/3 a^2h.