Answer:
Step-by-step explanation:
x-y=7
-3x+9y=-39
Divide the second equation by 3
-x +3y = -13
Add this to the first equation
x-y=7
-x +3y = -13
----------------------
0x +2y = -6
Divide by 2
2y/2 = -6/2
y = -3
Now find x
x-y = 7
x -(-3) = 7
x+3 = 7
Subtract 3 from each side
x = 4
(4,-3)
Or by substitution
x-y=7
solve for x
x = 7+y
-3x+9y=-39
Substitute y+7 in for x
-3(7+y) +9y = -39
Distribute
-21 -3y +9y = -39
Combine like terms
-21 +6y = -39
Add 21 to each side
6y = -18
Answer:
a is to be as b as 1 is to 3 (a:b as 1:3)
Step-by-step explanation:
Answer:
it's quadratic
Step-by-step explanation:
sorry i answered late but i hope this helps other people
Answer:
Step-by-step explanation:
Let's say you are given the equation 4(x+5). What you must do is distribute the 4 to everything inside the parenthesis. What this means is that you multiply everything inside the parenthesis by the number outside the parenthesis (in this equation that would be 4). For example, the equation 4(x+5) would distribute as (4*x)+(4*5). This would then become 4x+20.