Respuesta :
a. A = lw, because it is a square l = w, so 400 = x^2.
b. square root both sides. sq rt of 400 = + 20 or - 20. so x = + 20 or - 20.
c. No, -20 does not make sense because distance (length and width) cannot be negative.
d. Perimeter is the distance around a shape. Find the perimeter. For a square, P = 4x, so P = 4(20) = 80. So the length of wood needed to go around the painting is 80 inches.
An artist wants to frame a square painting with an area of 400 square inches.
(a) x is the length of one side of the painting
Area of the square formula is [tex]A = (side)^2[/tex]
side is x. so area becomes [tex]A = (x)^2[/tex]
We know Area is 400. so the equation becomes
[tex]400 = (x)^2[/tex]
(b) Solve the equation [tex]400 = (x)^2[/tex] for x
[tex]400 = (x)^2[/tex] (take square root on both sides)
When we take square root we put +-
+-20 = x
x = +20 in and x=-20in
So there are two solutions for the above equation.
(c)No. we know x is length of the side. the length cannot be negative .
So x=-20 inch is not valid
x=20 inches is our only solution.
(d)To find the length of the wood trim needed to go around the painting, we find the perimeter of the square
Perimeter = 4* side
= 4* x = 4* 20 = 80 inches