8x + 2y = 44
5x + 2y = 35
Since 2y is already common, there is no need for multiplication. Just reverse the signs on the equation.
Like this;
8x + 2y = 44
-5x - 2y = -35
All the additions become subtractions and vice versa.
-2y and +2y get cancelled.
Leaving;
8x = 44
-5x = -35
Now, subtract again.
8x - 5x = 3x
44 - 35 = 9
So;
3x = 9
x = 9 / 3
x = 3
We found 'x' and now we have to find 'y'.
Just substitute.
[8 x 3] + 2y = 44
24 + 2y = 44
2y = 44 - 24
2y = 20
y = 20 / 2
y = 10
Now, we re-check;
[8 x 3] + [2 x 10] = 44
24 + 20 = 44
Explaining the error for #9b is simply doing the whole sum.
Hope this helped! :) I tried my best to explain.
Answer:
-4 =x
Step-by-step explanation:
2x - 5= 5x + 7
Subtract 2x from each side
2x-2x - 5= 5x-2x + 7
-5 = 3x+7
Subtract 7 from each side
-5-7 = 3x+7-7
-12 = 3x
Divide by 3
-12/3 = 3x/3
-4 =x
Answer:
9r²(r - 8)
Step-by-step explanation:
Step 1: Write expression
9r³ - 72r²
Step 2: Factor out 9
9(r³ - 8r²)
Step 3: Factor out r²
9r²(r - 8)
Answer:
x=0.25 or -1/4
Step-by-step explanation:
120x + 21 = -9
120x = -30 (-21 from both sides of equation)
x = -0.25 or -1/4 (divide 120 from both sides of equation)