Let x represent the amount of money you originally had. The algebraic expression would be: x-20+3×=80.
If you want to solve the equation, it would be: 4x=100, and x=100÷4, which equals 25. So your original money was $25.
Where is X in the equation?
Answer:
-4
Step-by-step explanation:
y=3x - 1 x= -1
y = 3(-1) -1
y = -3 -1
y= -4
Let y represents the number of students that aren't members.
x + y = the total number of student
y = the total number of student - x
i hope my answer is what you need...
The second system of equations,

is correct.
We know that Bethany's age is x. Since Laura is 13 years older, her age is x+13. The product of their ages is equal to twice Amanda's age, and Amanda's age is y. This gives us:
x(x+13) = 2y
Using the distributive property, we have
x²+13x=2y
Dividing everything by 2 (to isolate y), we have:
x²/2 + (13/2)x = y
If we take 20 years off of Bethany's age, it is now represented as x-20. Taking 20 years off of Laura's age would be (x+13-20) or x-7. The product of their ages now is equal to David's age; David is 11 years older than Amanda, so his age is y+11. This gives us:
(x-20)(x-7)=y+11
Multiplying the binomials we have:"
x*x - 7*x - 20*x - 20(-7) = y+11
x²-7x-20x--140=y+11
x²-27x+140=y+11
To isolate y, subtract 11 from both sides:
x²-27x+140-11 = y+11-11
x²-27x+129 = y