<span>(x + 8) (x + 6) = 160
x² +6x +8x +48 = 160
</span>x² +6x +8x +48 - 160 =0
<span>x² +14x -112=0
You have to calculate the discriminant.
(Please mark be brainliest)
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Surface area is just the area of all these 4 triangles plus the rectangle.
First we can find the area of the rectangle.

Half of the length is 28 cm, so the full length must be 28 * 2 = 56 cm.


The base for the left and right triangles are 27. The heights would be the net length minus half the length of the rectangle:

Calculate the area:



We have two of these triangles.

Now do the other two pair of triangles. The bases for them are 28 + 28 = 56 cm. The heights would be the net width minus the width of the rectangle:

Now find the area:



We have two of these triangles.

Add all the areas together: