Question

What does x have to be so their perimeter is the same

Answer 1

Hey there!!

perimeter of rectangle = 2 ( l + b )

perimeter of a triangle = add up all the sides

2 ( x + 2 + x + 1 ) = x +  7 + x + 3 + x + 9

2 ( 2x + 3 ) = 3x + 19

4x + 6 = 3x + 19

x = 19 - 6

x = 13

Hope my answer helps!

Answer 2

Ok so first add up all the sides on each shape

Rectangle 4x+6
Triangle 3x+19

Make the perimeters equal one another

4x+6=3x+19
Then find x

4x+6=3x+19
-6. -6

4x=3x+13

-3x. -3x

X=13
So x must be 13 for the perimeters to be equal

You can even replace x with 13 to check

So for the rectangle 4*13+6 =58
And for the triangle 3*13 +19=58