Two perpendicular lines PQ and QR intersect at (1, -1). If the equation of PQ is x - 2y + 4 = 0, find the equation of QR.

2x + y - 1 = 0

Step-by-step explanation:

The equation of a line in slope- intercept form is

y = mx + c ( m is the slope and c the y- intercept )

Given

x - 2y + 4 = 0 ( subtract x + 4 from both sides )

- 2y = - x - 4 ( divide all terms by - 2 )

y = x + 2 ← in slope- intercept form

with slope m =  

Given a line with slope m then the slope of a line perpendicular to it is

= - = - = - 2 , thus

y = - 2x + c ← is the partial equation of the perpendicular line

To find c substitute (1, - 1) into the partial equation

- 1 = - 2 + c ⇒ c = - 1 + 2 = 1

y = - 2x + 1 ← in slope intercept form

Subtract - 2x + 1 from both sides

2x + y - 1 = 0 ← in general form

gregory's graph is incorrect because it shows 2 inches of growth for each week when it should show 0.75 inches of growth each week.

rick has $1400 and sally has $1500

step-by-step explanation:

to find amount of money rick has after 10 years :

principal = $1000 , time = 10 years , rate = 4% annually

to find amount of money sally has after 10 years :

her friend gives to pay her $50 per year, therefore money she has after 10 years = 50 × 10 = $500

also, sally gets $1000 after 10 years,

therefore, total amount of money sally has after 10 years = 500 + 1000 = $1500

so, after 10 years : rick has $1400 and sally has $1500