1. since the equations equal each other
2x+19=x+7
-x -x
x+19=7
-19 -19
x= -12
sub into y= x+7
y= -12+7
y= -5
2. x+2y=-7
<span>x+y+23=0
i don't know what the second equation is equal to, i'll assume 0
2y=x-7
y=1/2x-7/2
sub this into x+y+23=0
x+1/2x-7/2+23=0
3/2x+39/2=0
-39/2 -39/2
3/2x= -39/2
x=-39/2 / 3/2
x= -13
sub into y=1/2x-7/2
y=1/2(-13)-7/2
y= -10
3. </span>x+5y=2
<span>x=-4y+5
</span>sub x=-4y+5 into x+5y=2
-4y+5+5y=2
y+5=2
-5 -5
y= -3
sub y =-3 into x =-4y+5
x=-4(-3)+5
x= 17
4. 3x+y=9
<span>y=-5x+9
</span>sub -5x+9 into 3x+y=9
3x+(-5x+9)=9
3x-5x+9=9
-2x+9=9
-9 -9
-2x=0
x=0
sub into y=-5x+9
y=-5(0)+9
y=9
Answer:
28+12x
Step-by-step explanation:
Multiply 7 with 4
Multiply 3x with 4
Step-by-step explanation:
x = number
3x - 15 = (x - 12)×-4 or (12-x)×-4
3x - 15 = -4x + 48 or -48 + 4x
7x = 63, x = 9 or
33 = x
Answer:
Y means profits and x is the number sold.
Step-by-step explanation:
(2$ times x) - 7=y.
Answer:
Equation: 
Solution: 
Step-by-step explanation:
Let be "t" the number of movie tickets bought by the group of friends.
According to the information given in the exercise, the price of each movie ticket is: $8.50.
Then, you can represent the amount (in dollars) the group of friends spent in movie tickets, with this expression:

You know that one person spent $6.50, then the expression that represents the total amount (in dollars) the group of friends spent in food and movie tickets, is:

Since that total amount spent is given in the exercise, you can write the following equation to determine how many tickets were bought:

Finally, you can solve for "t" in order to find the solution of the equation. This is:
