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The line y = 5x – 3 and y = 2x + 9 intersects at P. What are the coordinates o...


Question

The line y = 5x – 3 and y = 2x + 9 intersects at P. What are the coordinates of P?

Options

A) (2, 7)

B) (2, 13)

C) (4, 17)

D) (-4,-23)

The correct answer is C.

Explanation:

y = 5x - 3
y = 2x + 9
y = y
y = 5x - 3. . . . eqn 1
y = 2x + 9 . . . . eqn 2
5x - 3 = 2x + 9
Collect Like Terms
5x - 2x = 3 + 9
3x = 12
x = 12/3
x = 4

Sub for y in any of eqn 1 & 2
From eqn 2
y = 2x + 9
y = 2(4) + 9
y = 8 +9
y = 17

Therefore, The coordinates are (4, 17)

Explanation provided by Pirisola Ayomikun


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Discussion (2)

  • y = 5x - 3
    y = 2x + 9
    y = y
    y = 5x - 3. . . . eqn 1
    y = 2x + 9 . . . . eqn 2
    5x - 3 = 2x + 9
    Collect Like Terms
    5x - 2x = 3 + 9
    3x = 12
    x = 12/3
    x = 4

    Sub for y in any of eqn 1 & 2
    From eqn 2
    y = 2x + 9
    y = 2(4) + 9
    y = 8 +9
    y = 17

    Therefore, The coordinates are (4, 17)

  • Derick

    Make it a simultaneous equation:
    y - 5x = -3
    y - 2x =9
    -3x = -12
    x = 4
    Substitute x in d equation above and
    y - 2(4) = 9
    y - 8 = 9
    y = 17