Question

4x - 7 's square diagnosis​

Answer 1

Answer:

(5x-4)(4x-7) = 209

20x^2 + 19x - 237 = 0

(20)(x-3)(x+3.95) = 0

Therefore, either (x-3) or (x+3.95) must be equal to 0, which means x = 3 or

x = -3.95. Since setting x equal to -3.95 would result in negative lengths of the sides of the rectangle (which is impossible), x must be equal to 3.

Since x = 3, the sides of the rectangle are:

(5*3–4) = 11 and (4*3+7) = 19. The perimeter is then as follows:

P = 2(11) + 2(19) = 60.

Therefore, x = 3 and the perimeter is 60 cm.

Step-by-step explanation:

(5x-4)(4x-7) = 209

20x^2 + 19x - 237 = 0

(20)(x-3)(x+3.95) = 0

Therefore, either (x-3) or (x+3.95) must be equal to 0, which means x = 3 or

x = -3.95. Since setting x equal to -3.95 would result in negative lengths of the sides of the rectangle (which is impossible), x must be equal to 3.

Since x = 3, the sides of the rectangle are:

(5*3–4) = 11 and (4*3+7) = 19. The perimeter is then as follows:

P = 2(11) + 2(19) = 60.

Therefore, x = 3 and the perimeter is 60 cm.