More practice with graphing linear equations.

They are linear functions.

We need only two points to plotting a graph.

5.

y = -x + 6

Choose any two values of x and calculate y.

for x = 0 → y = -0 + 6 = 6 → (0, 6)

for x = 6 → y = -6 + 6 = 0 → (6, 0)

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6.

Convert the equation of line from the standard form to slope-intercept form.

y = mx + b

-15x + 10y = -60      add 15x to both sides

10y = 15x - 60       divide both sides by 10

y = 1.5x - 6

Choose any two values of x and calculate y.

for x = 0 → y = 1.5(0) - 6 = 0 - 6 = -6 → (0, -6)

for x = 4 → y = 1.5(4) - 6 = 6 - 6 = 0 → (4, 0)

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7.

x = -5

It's a vertical line

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8.

15y - 12x = -60      add 12x to both sides

15y = 12x - 60       divide both sides by 15

y = 0.8x - 4

Choose any two values of x and calculate y.

for x = 0 → y = 0.8(0) - 4 = 0 - 4 = -4 → (0, -4)

for x = 5 → y = 0.8(5) - 4 = 4 - 4 = 0 → (5, 0)

36 is the final answer! : )

hello from mrbilldoesmath!

answer:

25x^2 + 90x + 84

discussion:

mn(x) = m(n(x)) = m( 5x + 9) =

(5x + 9)^2 + 3 =>

25x^2 + 90x + 9^2 + 3 =

25x^2 + 90x + 84                 (as 9^2 = 9*9 = 81)

which is the second choice

regards,  

mrb

p.s.   i'll be on vacation from friday, dec 22 to jan 2, 2019. have a great new year!