X = -6y - 12
4x + 5y =-39
4x + 5y = -39
-4(-6y - 12) + 5y = -39
-4(-6y) + 4(12) + 5y = -39
24y + 48 + 5y = -39
29y + 48 = -39
29y = -87
y = -3
x = -6y - 12
x = -6(-3) - 12
x = 28 - 12
x = 6
(x, y) = (6, -3)
The value of the constant k when the value of x and y is 7 and 3 respectively in the equation xy=k is 21.
<h3>What is an equation?</h3>
An equation is formed when two equal expressions are equated together with the help of an equal sign '='.
The value of the constant k when the value of x and y is 7 and 3 respectively in the equation xy=k can be written as,

Hence, the value of the constant k when the value of x and y is 7 and 3 respectively in the equation xy=k is 21.
Learn more about Equation:
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Answer:
can u please attached the figure
Answer:
x=2
Step-by-step explanation:
3x=4+2(3-x)
Distribute 2 to 3 and x
3x=4+6-2x
Add 2 to both side of the equal sign and combine 4 and 6
5x=10
divide both sides by 5
x=2