Is (-4,7) a solution to the equation
3(x - 10) = 6y
The 1st number of (-4,7) is -4. So -4 is the number you substitute for x.
The 2nd number of (-4,7) is 7. So 7 is the number you substitute for y.
In
3(x - 10) = 6y
replace the x by -4:
3(-4 - 10) = 6y
replace the y by (7):
3(-4 - 10) = 6(7)
Combine the numbers inside the parentheses:
3(-14) = 6(7)
Multiply the 3 by the -14
-42 = 6(7)
Multiply the 6 by the 7
-42 = 42
No they aren't equal. Their absolute values are equal,
but their signs aren't. So this is NOT a solution. Next
I'll give you an ordered pair which IS a solution:
--------------------------
Suppose you were given (2,-4) instead.
The 1st number of (2,-4) is 2. So 2 is the number you substitute for x.
The 2nd number of (2,-4) is -4. So -4 is the number you substitute for y.
In
3(x - 10) = 6y
replace the x by 2:
3(2 - 10) = 6y
replace the y by (-4):
3(2 - 10) = 6(-4)
Combine the numbers inside the parentheses:
3(-8) = 6(-4)
Multiply the 3 by the -8
-24 = 6(-4)
Multiply the 6 by the (-4)
-24 = -24
These are equal. So this IS a solution.
Edwin
AnlytcPhil@aol.com
