You get everything you need from factoring the last expression:
The left side is a difference of squares, and we get another difference of squares upon factoring. We end up with
Plug in everything you know and solve for 
:
Answer:
a) 512 cm^3
b) 469.125 cm^3
Step-by-step explanation:
8*8*8 = 512 cm^3
or
8^3 = 512 cm^3
3.5^3 = 42.875
512 - 42.875 = 469.125 cm^3
You can round the second answer down
Answer:
8,920 ÷ 80=111.5
892 ÷ 8=111.5
89.2 ÷ 0.08=111.5
.892 ÷ 0.008=111.5
Step-by-step explanation:
Answer:
1.
8x + 6y = 28
9x + 3y = 39
Set to equal y.
8x + 6y = 28
6y = -8x + 28
y = -8/6x + 28/6
y = -4/3x + 14/3
9x + 3y = 39
3y = -9x + 39
y = -9/3x + 39/3
y = -3x + 13
Set equal to each other.
-4/3x + 14/3 = -3x + 13
Combine like terms.
5/3x = 25/3
Multiply by 3/5
x = 5
Plug x in.
y = -3(5) + 13
y = -15 + 13
y = -2
(5, -2)
2.
-2x - 9y = -3
-7x - 9y= -33
Set equal to y.
-2x - 9y = -3
-9y = 2x - 3
y = -2/9x + 3/9
y = -2/9x + 1/3
-7x - 9y= -33
-9y = 7x - 33
y = -7/9x + 33/9
y = -7/9x + 11/3
Set equal to each other
-2/9x + 1/3 = -2/9x + 1/3
0 = 0
infinitely many solutions
