3y = 2x + 6
x + y = 7
y = 7 - x
3(7 - x) = 2x + 6
21 - 3x = 2x + 6
21 - 6 = 2x + 3x
15 = 5x
15/5 = x
3 = x
x + y = 7
3 + y = 7
y = 7 - 3
y = 4
Solution is (3,4)
Volume of rectangular prism = 1 1/3 x 5/6 x 2/3 = 4/3 x 5/6 x 2/3 = 20/27
Volume of cube = 1/6 x 1/6 x 1/6 = 1/216
Number of cubes that will pack the rectangular prism = 20/27 / 1/216 = 160
for number 19, figure out the exponents then multiply.
for scientific notaintion you figure out how many numbers are behind the decimal , then do that number as an exponient to 10 then multiply by that number. i hope i made a bit of sense. if not look at kahn academy for help !
Use the distributive property.
9/10 (x + 8) = 18
9/10x + 7.2 = 18
9/10x + 7.2 - 7.2 = 18 - 7.2
9/10x = 10.8
9/10x / 9/10 = 10.8 / 9/10
x = 12
Hi there!
I'm just gonna answer this and explain as I'm doing it.
So we have (3x10)x8= __x(10x8)
Well, first we look at what they did. They couldn't have changed the equation, but just moved things around.
Now, assuming you know your properties, I'm gonna go ahead and answer it.
(3x10)x8=3x(10x8)
^^
I used the Associative property, which basically says that when 3 or more #s are multiplied, the answer doesn't change no matter how you group the numbers. See how they just moved the numbers around, and only swapped the 3 for the 8?
Hope this helped!
