Elimination 4x-7y=5 9x-7y=-15

Mathematics

1 answer:

Afina-wow [57]4 years ago

7 0

Answer:

x = -4

Step-by-step explanation:

To make this easier to explain and easier to solve, we're going to first multiply the second equation of 9x-7y=-15 by -1 to make the y coefficient positive.

This results in -9x+7y=15.

When we line up the two equations on top of each other now, we'll see that both the first and second equations have opposite y coefficients, which is vital for elimination.

The next step is to add the second equation to the first one. Teachers may tell you to subtract, but I find it easier to add if you make the two y coefficients of negative value to each other.

4x-7y=5

+ -9x+7y=15

___________

-5x+0y=20, or just -5x=20, because you have successfully eliminated the y variable.

From there, you're going to solve like a normal equation (divide both sides by -5) toget you x=-4.

You might be interested in

Let σ be portion of the paraboloid z = x 2 + y 2 − 9 lying on and below the xy-plane. Let σ have downward orientation. Let C be

Grace [21]

Answer:

See explaination

Step-by-step explanation:

Stoke theorem proposes that the surface integral of the curl of a function over any surface bounded by a closed path is equal to the line integral of a particular vector function round that path.

The Stoke Theorem can be used if you see a two dimensional region bounded by a closed curve, or if you see a single integral ie a line integral.

See attached file for further solution.