Given points are
Next, find the slope.
\Substitute 4 for y2, 2 for y1, 3 for x2, and
1 for x1 in slope formula.
(Product of two same signs is positive)
(Add:
)
(Subtract:
)
(Simplify) \ \
(Cancel common terms)
You know the slope and a point on the line, so use point - slope form
with either given point to write an equation of line.
\Choose
(Substitute 2 for y1,
1 for x1 and
)
(Product of two same signs is positive)
(Apply distributive property:
)
(Multiply:
)
(Add to 2 each side)
(Apply additive inverse property:
)
(Apply additive identity property:
)
To add fractions the denominators must be equal.
\Find the least common denominator (LCD).
\Write the prime factorization of each denominator.
\Multiply the highest power of each factor in either number.
\LCD of the fractions is 2.
\Rewrite the equivalent fractions using the LCD.
\Rewrite the expression using the LCD.
\ (Add:
)
The equation of line is .