SOLUTION: Hello: I really need your help. I have tried all possible ways to solve this equation but I am confused on how to start to solve it. Here is the question: Find the point of i

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Question 12985: Hello:
I really need your help. I have tried all possible ways to solve this equation but I am confused on how to start to solve it. Here is the question:
Find the point of intersection of the given straight lines.
x - 4y = -2
x + 2y = 4
Please help me with this problem. Thank you.
Found 2 solutions by rapaljer, sabanasir:
Answer by rapaljer(4671) (Show Source):
You can put this solution on YOUR website!
There are several ways to do this. The elimination method usually works well when the equations are both in standard form, as in this case.
x - 4y = -2
x + 2y = 4

In order to eliminate the x variable, multiply the first equation by -1, and rewrite the second equation as it is:
-x + 4y = 2
x + 2y = 4

Now add these two equations together giving you
6y = 6
y=1

Substitute the y = 1 back into either equation, say the first one:
x - 4y = -2
x - 4(1) = -2
x-4 = -2

Add 4 to each side:
x-4+4 = -2 + 4
x=2

Check in the second equation, by letting x= 2 and y = 1:
x + 2y = 4
2 + 2(1) = 4
It checks!

R^2 at SCC

Answer by sabanasir(22) (Show Source):
You can put this solution on YOUR website!
hmm it goes this way....
the idea first is to get a combined equation of the two either by adding them or subtracting them like...:
i can easily subtract the two equations:
(1) x-4y=-2
(2) x+2y=4
subtracting will get us free from one variable 'x' cancelled out.
+x-4y=-2
+x+2y=4
(-)
__________
-6y=-6
6y=6
y=1
okkkk now v get the value of y as 1.
we cud put y's value in either of the equation to get the value of 'x'
e.g i put it in (1)
x-4y=-2
put y=1
x-4(1)=-2
x-4=-2
x=-2+4
x=2
so the intersecting points are (x,y)=(2,1)