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2 years ago

Can some one help me with this and explain it?

Mathematics

1 answer:

Tresset [83]2 years ago

3 0

Answer:

A. (3,2)

Step-by-step explanation:

One way to solve without graphing

equate both equations to each other:

$2x - 4 = - x + 5$

add x on both sides:

$2x + x - 4 = 5$

add 4 on both sides:

$2x + x = 5 + 4$

collect like terms:

$3x = 9$

divide 3 on both sides, so

$x = 3$

now that we have x, go back to any one of the equations and substitute x=3 to find y. I'll use y=2x-4

$y = 2x - 4$

sub x=3

$y = 2(3) - 4$

2 × 3 is 6

$y = 6 - 4$

$y = 2$

we now have x and y, so the coordinates are (3,2)

If you want to use the graphing method, substitute in x values of your choice, for example -2 to 2 into each equation to find y and when there is a same coordinate in both equations that is the solution.

y = 2x - 4

when x is -2, y = 2(-2)-4 = -8. (-2,-8)

when x is -1, y = 2(-1) - 4= -6. (-1,-6)

when x is 0, y = 2(0)-4 = -4. (0,-4)

when x is 1, y = 2(1) - 4 = -2. (1,-2)

when x is 2, y = 2(2) - 4 = 0. (2,0)

when x is 3, y = 2(3) - 4 = 2. (3,2)

do the same thing of substituting to the other equation

y = -x + 5

when x is -2, y is 7 (-2,7)

when x is -1, y is 6. (-1,6)

when x is 0, y is 5. (0,5)

when x is 1, y is 4. (1,4)

when x is 2, y is 3. (2,3)

when x is 3, y is 2. (3,2)

plot these coordinates on a graph

they both have same x value (3) and same y value (2)

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3 years ago

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each factor is an expression of x that turns 0 for the given value of x.

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2 years ago

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3 years ago

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2 years ago

Can some one help me with this and explain it?​

Can some one help me with this and explain it?