Question

Math teacher doesn't explain this very well, please help solve.

Answer 1

a) Since we know they have equal perimeters, we can set them equal to each other. First, let's recap the perimeters of squares and triangles (s = side):
$P_s = 4s/tex] [tex]P_t = 3s=s+s+s$

Now, we can set up our equation:
$4(x-3) = 8 + x + x$
$4x-12 = 8+2x$

We can solve for x:
$2x-12=8$
$2x = 20$
$x = \frac{20}{2} = 10$

So, x = 10.

b) We known the perimeter formulas and we have what x is. So, let's just plug and chug.
Square:
$4(x-3) = 4(10-3) = 40-12 = 28$
So, the perimeter of the square is 28 units².
Since their perimeters are equal the perimeter of the triangle is also 28 units²