1. if 4 + 4 = x you'd say x = 8
pre-algebra wants you to get used to using letters like x in math
where x = the answer
put x on one side of the equal sign & the numbers on the other side
letters like x help people do bigger & is more complicated math
2. in real life math the symbols
less than or < means "up to" or "at most" &
great than or > means "at least"
which helps with things like money & prices
like "that chair is at least $100" or "chair > $100"
3. negative numbers are backwards:
-4 -5 -6 are considered smaller than -3
Answer:
in pre algebra
you have to do the math so that you
put x on one side of the equal sign &
the numbers on the other side
x = the answer
for
1.
2x - 7 = 3 (x - 4)
multiply 3 with (x - 4)
you do this by
multiplying 3 with x and
multiplying 3 with- 4
2x - 7 = 3 (x - 4)
2x - 7 = 3x - 12
put x on one side of the equal sign & the numbers on the other side
2x - 7 = 3x - 12
-2x = -2x
2x -2x = 0 & 7 comes down.
3x -2x = 1x & - 12 comes down
0 - 7 = 1x - 12
add 12 on both sides
- 12 + 12 = 0
- 7 + 12 is the same as 12 - 7 which is 5
0 + 5 = 1x - 0
you dont have to show the 0
& if its 1x you you dont have to show the 1
5 = x or x = 5
2.
5x + 3 < 4x - 1
for now treat < like an equal sign
in real life math the symbols < & > mean at least or at most
which helps with things about money
5x + 3 < 4x - 1
subtract -4x on both sides
5x + 3 < 4x - 1
-4x -4x
1x + 3 < 0 - 1
subtract 3 on both sides
1x + 3 < 0 - 1
1x - 3 < 0 - 3
x < - 3
answer means the answer is
at most -4
up to -4
& less than -3 because
-4 is the highest number thats less than -3
negative numbers are backwards
-4 -5 -6 are considered smaller than -3
Explanation:
x is called a variable
if someone wrote
4 + 4 = x
you'd say x = 8, right?
pre-algebra wants you to get used to using letters like x in math
because letters like x help people do math that has much bigger numbers & is more complicated
this higher math companies like banks & hospitals help people deal with money & medicine
problems in pre-algebra
the answers usually look like
x = the answer