Answer:
Step-by-step explanation:
4x − y = −11
2x + 3y = 5
lets multiply the second equation by -2 and add it to the first:
4x − y = −11
-4x - 6y = -10
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0 - 7y = -21
y = -21/-7
y = 3
now we substitute this result in the first equation to find x:
4x − y = −11
4x - 3 = -11
4x = -8
x = -8/4
x = 2
so the solution is y = 3 and x =2
4x − 9y = −21
−10y = −30
we solve for y
−10y = −30
y = -30/-10
y = 3
and substitute in the first equation:
4x − 9y = −21
4x − 9(3) = −21
4x - 27 = -21
4x = 6
x = 6/4 = 3/2
so the solution is x = 3/2 and y = 3
4x + 3y = 5
2y = −6
we solve for y:
2y = −6
y = -6/2
y = -3
we do substitute in the first equation:
4x + 3y = 5
4x + 3(-3) = 5
4x - 9 = 5
4x = 14
x = 14/4
x = 7/2
so the solution is x = 7/2 and y = -3
7x − 3y = −11
9x = −6
we solve for x:
9x = −6
x = -6/9
x = -2/3
then we substitute in the first equation the result found:
7x − 3y = −11
7(-2/3) − 3y = −11
-14/3 - 3y = -11
we multiply by 3 to eliminate fractions:
-14 - 9y = -33
9y = 19
y = 19/9
so the solution is x = -2/3 and y = 19/9
12x − 3y = −33
14x = −28
we solve for x:
14x = −28
x = -28/14
x = -2
then we substitute in the first equation:
12x − 3y = −33
12(-2) − 3y = −33
-24 - 3y = -33
3y = 9
y = 3
then the solution is x = -2 and y = 3
19) 15 <= 9 + 3x
15) x = 23,24,25
17) x <= 115
9) Second line
11) g > 20, don't fill in dot, any number greater than 20
1) -3 + h<= 3.4
3) No, x > -2
5) x > 14, don't fill in dot, any number greater than 14
7) k<=20, fill in dot, 20 or any larger number
(took me while to type this out lol cause on mobile)
1 is the answer 1111111111
Step-by-step explanation:
1. 1/4(x + 12)=2 - first isolate X'
- 12 -12
2. 1/4(x) = -10 - 1/4 since its a fraction, you'll have to subtract not divide
-1/4 - 1/4
3. x = -10.25
Andre did the first step correctly, but on the second step he just divided 1.4 by -10, instead of subtract 1/4 from both sides.
3+(-4)=(-1)
so, 3 is the missing number
