An equvilent equation
remember you can do anything to an equation as long asyou do it to both sides
assuming yo have
x+y=1 and
x-3y=9
mulitply both by 2
2x+2y=2
2x-6y=18
those are equvilent
ok, solve initial
x+y=1
x-3y=9
multiply first equation by -1 and add to 2nd equation
-x-y=-1
<u>x-3y=9 +</u>
0x-4y=8
-4y=8
divide both sides by -4
y=-2
sub back
x+y=1
x-2=1
add 2
x=3
x=3
y=-2
(3,-2)
if we test it in other one
2x+2y=2
2(3)+2(-2)=2
6-4=2
2=2
yep
2x-6y=18
2(3)-6(-2)=18
6+12=18
18=18
yep
solution is (3,-2)
Answer:
0.01
Step-by-step explanation:
Y and X is y
Answer:
- x > -2
- n ≤ -2 or n ≥ 8
Step-by-step explanation:
<h3>1.</h3>
Add 7x-2 to both sides and collect terms.
2x +2 -6x +7x -2 > -4 -7x +7x -2
3x > -6
x > -2 . . . . . . . divide by 3
__
<h3>2.</h3>
Solve these one at a time, and form the union of the answers.
1 +7n ≤ 15 . . . .given
7n ≤ 14 . . . . . . subtract 1
n ≤ 2 . . . . . . . divide by 7
__
-2n -2 ≤ -18 . . . given
-2n ≤ -16 . . . . . add 2
n ≥ 8 . . . . . . . . divide by -2
The solution is n ≤ -2 or n ≥ 8.
