Answer:
1/2 - 3(1/2 + 1)²
simplify the expression (1/2 + 1)
1/2 - 3•(3/2)²
using PEMDAS, we see we have to evaluate the exponent first
(3/2)² = 9/4
rewrite the equation
1/2 - 3 • (9/4)
multiply 3 by (9/4)
1/2 - (27/4)
subtract
-25/4
(1 + 1/3)² - 2/9
simplify the expression (1 + 1/3)
(4/3)² - 2/9
using PEMDAS, we see we have to evaluate the exponent first
(4/3)² = 16/9
rewrite the equation
(16/9) - (2/9)
subtract
14/9
Solve for y in the first equation.
y = 4x + 6
Substitute <span>4x + 6 into the second equation.
-5x - (</span><span>4x + 6) = 21
Distribute
-5x - 4x - 6 = 21
Combine like terms
-9x = 27
Divide both sides by -9
x = -3
Substitute back into first equation
-4(-3) + y = 6
Solve for y
y = -6</span>

Put the values of c = 6 and d = 7 to the expression:

Answer:
Step-by-step explanation:
hello:
x²-4x=0 means : x(x-4)=0
x=0 or x-4=0
conclusion : x=0 and x= 4 ...answer : B