Find the equation of a line with the properties given Write

Find the equation of a line with the properties given. Write the equation in the form indicated.

11) Through (4, -3) and parallel to the line whose equation is y = -3x + 7; slope-intercept form

Solution

Let the equation of the required line be y = mx + c where m is its slope and c isits y-intercept. Since this line is parallel to the line y = -ex +7, its slope is -3 ( parallel lines have the same slope). Then the equation of the required line changes to y = -3x +c. Further, since this line passes through the point (4,-3) , on substituting x = 4 and y = -3 in its equation, we get -3 = -3*4 +c or, c = -3+ 12 = 9. Then the equation of the required line is y = -3x +9.