Q. A line that includes the points (−1,2) and (−3,a) has a slope of −2. What is the value of a?a = ____
Understand the formula: Understand the formula for the slope of a line.The slope m of a line passing through two points (x1,y1) and (x2,y2) is given by the formula m=x2−x1y2−y1.
Apply the slope formula: Apply the slope formula to the given points and slope.We know the slope m is −2, and we have the points (−1,2) and (−3,a). Let's denote (−1,2) as (x1,y1) and (−3,a) as (x2,y2). According to the slope formula:−2=−3−(−1)a−2
Simplify and solve: Simplify the denominator and solve for a.−2=−3+1a−2−2=−2a−2Now, multiply both sides by −2 to isolate (a−2).−2×−2=(a−2)×−2−24=a−2
Find the value of a: Add 2 to both sides to find the value of a.4+2=a−2+26=a
More problems from Find a missing coordinate using slope