Write an equation for the line that contains (-15, -8) and is parallel to the graph -3x + 5y = -8

y=3/5x+1

Step-by-step explanation:

Hi there!

We are given the equation -3x+5y=-8 and we want to find the equation of the line that is parallel to -3x+5y=-8 and contains the point (-15,-8)

parallel lines have the same slopes, but different y intercepts.

So let's first find the slope of -3x+5y=-8

We can do this by converting the equation from standard form (ax+by=c where a, b, and c are free coefficients (numbers)) to slope-intercept form (y=mx+b, where m is the slope and b is the y intercept)

add 3x to both sides

5y=3x-8

divide by 5 on both sides

y=3/5x-8/5

3/5 is in the place of where m is, so that means that 3/5 is the slope of the line

we can write the equation of the new line in slope-intercept form.

Here it is so far:

y=3/5x+b

we need to find b

Because the line will pass through the point (-15,-8), we can use it to solve for b

substitute -15 as x and -8 as y

-8=3/5(-15)+b

multiply

-8=-9+b

add 9 to both sides

1=b

substitute 1 as b into the equation

y=3/5x+1

There's the equation of the line :)

Hope this helps!

answer is 144

step-by-step explanation:

part a

answer: a reasonable domain is where n is a real number. so n can be between 0 and 10. both endpoints are included.

work shown:

n is the number of days after the experiment starts. the smallest n can be is n = 0 which means that 0 days have gone by, and we're at the start. to find out how large n should be, then replace f(n) with 16.13 and solve for n. use logarithms to isolate the exponent.

f(n) = 12*(1.03)^n

16.13 = 12*(1.03)^n

16.13/12 = (1.03)^n

1.34416666666667 = (1.03)^n

(1.03)^n = 1.34416666666667

log[ (1.03)^n ] = log[ 1.34416666666667 ]

n*log[ 1.03 ] = log[ 1.34416666666667 ]

n = log[ 1.34416666666667 ]/log[ 1.03 ]

n = 10.0062999823929

this rounds to n = 10 which is fairly close but not 100% perfect. so this is the largest n can be.

note: if you plug n = 10 into f(n), you'll get roughly 16.127 which rounds to 16.13 (this comes up again in part c)

=====================================

part b

answer: the y intercept is 12. it represents the starting height of the plant in cm.

work shown:

plug n = 0 into the f(n) function. simplify

f(n) = 12*(1.03)^n

f(0) = 12*(1.03)^0

f(0) = 12*(1)

f(0) = 12

on day n = 0, aka the starting point, the height f(n) is 12 cm

=====================================

part c

answer: the average rate of change is approximately 0.43061036458991 (round however you need to). this represents the average growth rate from day n = 3 to day n = 10. so the plant grew roughly 0.43 cm per day during this timespan, assuming you round to 2 decimal places.

work shown:

compute f(3)

f(n) = 12*(1.03)^n

f(3) = 12*(1.03)^3

f(3) = 13.112724 < we'll use this later

compute f(10)

f(n) = 12*(1.03)^n

f(10) = 12*(1.03)^10

f(10) = 16.1269965521294 < we'll use this later

now use the formula below with a = 3 and b = 10

aroc = average rate of change

aroc = [ f(b) - f(a) ]/[ b - a ]

aroc = [ f(10) - f(3) ]/[ 10 - 3 ]

aroc = (16.1269965521294 - 13.112724)/(10 - 3)

aroc = 3.0142725521294/7

aroc = 0.43061036458991

round this however you need to

note: the plant grew approximately 3.01 cm over 7 days, so roughly 0.43 cm per day is the average growth rate (if you were to round to 2 decimal places).