Question

Line QR goes through points Q(0,1) and R(2,7). Which equation represents line QR? Worth 50 points!!

Answer 1

Option B

Th equation of line QR is y - 1 = 3x

Solution:

Given that Line QR goes through points Q(0, 1) and R(2, 7)

We have to find the equation of line

Let us first find the slope of line

The slope of line is given as:

$m=\frac{y_{2}-y_{1}}{x_{2}-x_{1}}$

Here given points are Q(0, 1) and R(2, 7)

$(x_1, y_1) = (0, 1)\\\\(x_2, y_2) = (2, 7)$

Substituting the values in slope formula, we get

$m = \frac{7-1}{2-0}\\\\m = \frac{6}{2} = 3$

Thus slope of line QR is 3

The equation of line in slope intercept form is given as:

y = mx + c ------ eqn 1

where "m" is the slope of line and "c" is the y - intercept

Substitute (x, y) = (0, 1) and m = 3 in eqn 1

1 = 3(0) + c

1 = 0 + c

c = 1

Substitute m = 3 and c = 1 in eqn 1

y = 3x + 1

y - 1 = 3x

Thus the equation of line is found. Option B is correct