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Sara is trying to find an equation for a line that passes through (5, 2) and is perpendicular to 3x + 2y = 15. Explain the steps that Sara could take to determine the equation.

Respuesta :

Answer: 2/3 x+7 1/2=y

Step-by-step explanation:

-1/3 x+2y=15

-1/3 x-15=-2y

2/3 x+7 1/2=y

Answer:

[tex]y-2=\frac{2}{3} (x-5)[/tex]

Step-by-step explanation:

Pre-Solving

We are given that a line is perpendicular to 3x + 2y = 15 and passes through (5,2). We want to write the equation of this line.

Perpendicular lines have slopes that multiply to equal -1.

So, we need to first find the slope of 3x + 2y = 15

Notice how the line is in standard form, which is ax + by = c. The slope of the line when the equation is in standard form is [tex]-\frac{a}{b}[/tex].

Since a = 3 and b = 2, the slope of the line is [tex]-\frac{3}{2}[/tex].

Now, we want to find the slope of the line perpendicular to this line.

Since the two slopes multiply to equal -1,

[tex]-\frac{3}{2} * m_2 = -1[/tex]

Multiply both sides by [tex]-\frac{2}{3}[/tex].

We get:

[tex]m_2=\frac{2}{3}[/tex]

Now, there are three ways to write the equation of the line:

  • Slope-intercept form, which is y = mx+b, where m is the slope and b is the value of y at the y -intercept.
  • Standard form, which is ax+by=c, where a, b, and c are free integer coefficients.
  • Point-slope form, which is [tex]y-y_1=m(x-x_1)[/tex], where m is the slope and [tex](x_1,y_1)[/tex] is a point.

As the question doesn't specify which form to use, any of the forms should work. However, let's use point-slope form, as that is the easiest form for us to use.

Solving

As we have found the slope and we were given a point, we can substitute these values into the formula.

[tex]y-y_1=m(x-x_1)[/tex]

[tex]y-2=\frac{2}{3} (x-5)[/tex]