Precalculus Examples
(-5,-7)(−5,−7) , 1212
Step 1
Find the value of mm using the formula for the equation of a line.
y=mx+by=mx+b
Step 2
Substitute the value of bb into the equation.
y=mx+12y=mx+12
Step 3
Substitute the value of xx into the equation.
y=m(-5)+12y=m(−5)+12
Step 4
Substitute the value of yy into the equation.
-7=m(-5)+12−7=m(−5)+12
Step 5
Step 5.1
Rewrite the equation as m(-5)+12=-7m(−5)+12=−7.
m(-5)+12=-7m(−5)+12=−7
Step 5.2
Move -5−5 to the left of mm.
-5m+12=-7−5m+12=−7
Step 5.3
Move all terms not containing mm to the right side of the equation.
Step 5.3.1
Subtract 1212 from both sides of the equation.
-5m=-7-12−5m=−7−12
Step 5.3.2
Subtract 1212 from -7−7.
-5m=-19−5m=−19
-5m=-19−5m=−19
Step 5.4
Divide each term in -5m=-19−5m=−19 by -5−5 and simplify.
Step 5.4.1
Divide each term in -5m=-19−5m=−19 by -5−5.
-5m-5=-19-5−5m−5=−19−5
Step 5.4.2
Simplify the left side.
Step 5.4.2.1
Cancel the common factor of -5−5.
Step 5.4.2.1.1
Cancel the common factor.
-5m-5=-19-5−5m−5=−19−5
Step 5.4.2.1.2
Divide mm by 11.
m=-19-5m=−19−5
m=-19-5m=−19−5
m=-19-5m=−19−5
Step 5.4.3
Simplify the right side.
Step 5.4.3.1
Dividing two negative values results in a positive value.
m=195m=195
m=195m=195
m=195m=195
m=195m=195
Step 6
Now that the values of mm (slope) and bb (y-intercept) are known, substitute them into y=mx+by=mx+b to find the equation of the line.
y=195x+12y=195x+12
Step 7