The area of square ABCD is 7cm².
Show that x² + 4x = 3

see explanation

Step-by-step explanation:

The area (A) of a square is calculated as

A = s² ( s is the measure of a side of the square )

Here s = x + 2 and A = 7, thus

(x + 2)² = 7 ← expand left side using FOIL

x² + 4x + 4 = 7 ( subtract 4 from both sides )

x² + 4x = 3 ← as required

x = -3

y = -18

step-by-step explanation:

to solve by substitution, substitute one variable and solve for the other. then substitute again to find the remaining variable.

x-1/3(3x-9) = -3 since y=3x-9 substittute y.

x-1/3(3x-9)=-3

x + x +3 = -3

2x+3=-3

2x+3-3= -3-3

2x=-6

x=-3

substitute again into y=3x-9

y=3(-3)-9

y=-9-9

y=-18

18.8cm hope i at all

step-by-step explanation: