1)
I:x-y=-7
II:x+y=7
add both equations together to eliminate y:
x-y+(x+y)=-7+7
2x=0
x=0
insert x=0 into II:
0+y=7
y=7
the solution is (0,7)
2)
I: 3x+y=4
II: 2x+y=5
add I+(-1*II) together to eliminate y:
3x+y+(-2x-y)=4+(-5)
x=-1
insert x=-1 into I:
3*-1+y=4
y=7
the solution is (-1,7)
3)
I: 2e-3f=-9
II: e+3f=18
add both equations together to eliminate f:
2e-3f+(e+3f)=-9+18
3e=9
e=3
insert e=3 into I:
2*3-3f=-9
-3f=-9-6
-3f=-15
3f=15
f=5
the solution is (3,5)
4)
I: 3d-e=7
II: d+e=5
add both equations together to eliminate e:
3d-e+(d+e)=7+5
4d=12
d=3
insert d=3 into II:
3+e=5
e=2
the solution is (3,2)
5)
I: 8x+y=14
II: 3x+y=4
add I+(-1*II) together to eliminate y
8x+y+(-3x-y)=14-4
5x=10
x=2
insert x=2 into II:
3*2+y=4
y=4-6
y=-2
the solution is (2,-2)
I’m Guessing The Answer Is A. (-2 , -3)
Cross multiply. Distribute...
OH GOD IT'S A QUADRATIC
<em>(our equation is in ax² + bx + c = 0 form. a=3. b= -38. c= -8.
</em><em>plug these values into the quadratic formula and simplify.)</em>
Approximate values for x: -0.20714 or 12.874
Step-by-step explanation:
y = 2x + 3
When x = 2
y = 2.2 + 3
y = 4 + 3
y = 7
When x = 0
y = 2.0 + 3
y = 0 + 3
y = 3
When x = -2
y = 2.(-2) + 3
y = -4 + 3
y = -1
When x = -4
y = 2.(-4) + 3
y = -8 + 3
y = -5
When x = -7
y = 2.(-7) + 3
y = -14 + 3
y = -9
