Answer:
Step-by-step explanation:
(0, -9) and (3,3)
(3+9)/(3-0) = 12/3 = 4
y + 9 = 4(x - 0)
y + 9 = 4x - 0
y = 4x - 9
Answer:
13 batches of cookies
Step-by-step explanation:
12 2/3 ÷ 2/3 = 12.6666667, it's 13 because 2/3 as a decimal is .6666666 and .6666667 is more than 2/3. So you add one to the answer.
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
Solve for x. Isolate the x. Note the equal sign. What you do to one side, you do to the other. Do the opposite of PEMDAS.
First, multiply 3 to both sides
6(3) = ((x + 2)/3)(3)
18 = x + 2
Finally, isolate the x. Subtract 2 from both sides
18 (-2) = x + 2 (-2)
x = 18 - 2
x = 16
16 is your answer for x
hope this helps
