Which equation in standard form has a graph that passes through the point (−4, 2)

and has a slope of 9 over 2
?
A.9x−2y=36

B.9x−2y=26

C.9x−2y=−40

D.9x−2y=−10

1 answer

To find the equation of a line in standard form that passes through the point \((-4, 2)\) with a slope of \(\frac{9}{2}\), we can start with the point-slope form of the equation:

\[ y - y_1 = m(x - x_1) \]

Here, \(m\) is the slope, and \((x_1, y_1)\) is the point the line passes through. Substituting in our values:

\[ y - 2 = \frac{9}{2}(x + 4) \]

Now, let's simplify this equation:

  1. Expand the right side: \[ y - 2 = \frac{9}{2}x + \frac{9}{2} \cdot 4 \] \[ y - 2 = \frac{9}{2}x + 18 \]

  2. Add 2 to both sides to isolate \(y\): \[ y = \frac{9}{2}x + 18 + 2 \] \[ y = \frac{9}{2}x + 20 \]

Now, we convert this into standard form \(Ax + By = C\). We start by multiplying the entire equation by 2 to eliminate the fraction:

\[ 2y = 9x + 40 \]

Next, we rearrange this equation to get it into standard form:

\[ -9x + 2y = 40 \]

To conform to the typical standard form \(Ax + By = C\), we can multiply by -1 to make the coefficient of \(x\) positive:

\[ 9x - 2y = -40 \]

Now we can match this with the options given:

  1. \(9x - 2y = 36\) (Not a match)
  2. \(9x - 2y = 26\) (Not a match)
  3. \(9x - 2y = -40\) (This matches)
  4. \(9x - 2y = -10\) (Not a match)

Thus, the correct equation in standard form that passes through the point (-4, 2) and has a slope of \(\frac{9}{2}\) is:

C. \(9x - 2y = -40\)