<span>y=x-4
y=-x+6
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Substitute x - 4 for y in </span>y=-x+6
x-4=-x+6<span>
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Add X on each side
</span><span>x-4+x</span>=-<span>x+6+x
</span>2x - 4 = 6
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Add 4 on each side
<span>2x-4+4</span>=<span>6+4
</span>2x = 10
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Divide by 2 on each side
2x ÷ 2 = 10 ÷ 2
x = 5
Now we have X
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To find Y we substitute 5 for x in y=<span>x-<span>4
</span></span>y = 5 - 4
y = 1
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Your answers are Y = 1 and X = 5
There is no solution for the first one
if you eliminate y you get 2 equations
-13x - 13z = -25
-13x - 13x = -15
- there is no solution to theses
a23 means the element in the second row and the 3rd column
so its -5
1.8- 3.7x = 4.2x + 0.3
Move 4.2x to the other side
Sign changes from +4.2x to -4.2x
1.8-3.7x-4.2x= 4.2x-4.2x+0.3
1.8-3.7x-4.2x= 0.3
1.8-7.9x= 0.3
Move 1.8 to the other side
Sign changes from +1.8 to -1.8
1.8-1.8-7.9x= 0.3-1.8
-7.9x= 0.3-1.8
-7.9x= -1.5
divide both sides by -7.9
-7.9/-7.9x= -1.5/-7.9
x= 0.18987341
Answer: x= 0.18987341
(x + 3) • (2x - 6x)
collect like terms
(x + 3) • (-4x)
distribute -4x through the parentheses
Answer: -4x^2 - 12x
Hope this helps!
