Find the point (x1, x2) that lies on the line x1+5x2=7 and on the line x1-2x2=-2. ?

Question

Please show me how you found answer. Will gladly give 5 points to most through.

Answer 1

you need to combine the equations so that one variable drops out, then solve for the 1 unknown.  For example:

X1 +  2X2 = 1

and

-X1 + 2X2 = 2

Can be combined by adding the second equation to the first.  When you add X1 and -X1, they cancel so you are left with:

4X2 = 3

X2 = 3/4

Now you can use this value of X2 to solve for X1 in either equation.  The values of X1 and X2 will be the points on the line.

Answer 2

Let's use x and y instead of x1 and x2.

x + 5y = 7

x - 2y = -2

Subtract second equation from first

7y = 9

y = 9/7

x + 45/7 = 7

x = 7 - 45/7 = (49 - 45)/7 = 4/7

The point is (4/7, 9/7)

Answer 3

X₁ + 5X₂ = 7

X₁ - 2X₂ = -2  ⇒  X₁ = 2X₂ - 2

By substitution,

(2X₂ - 2 ) + 5X₂ = 7

7X₂ = 9

X₂ = 9/7

X₁ = 2X₂ - 2

= 2(9/7) - 2

= 4/7

(X₁,X₂) = (4/7, 9/7)

Answer 4

um do your own homework don't use   the internet cheater!