after 4 weeks, the height of the plants had grown from 6 inches to 12 inches. Write and solve a proportion to find the percent increase in the height of the plants.

50%

Step-by-step explanation:

The 4 weeks in unnesseccary information when it comes to the formula of change over time.

Formula: P=N-O/O times 100

P= percentage, n=new unit(12), o=old unit(6),

First, Subtract 6 from 12 getting 6. Then, divide 6 by 12, getting 0.5. Lastly, multiply 0.5 by 100 to get 50, which is your percent of change.

y=x+9

?

step-by-step explanation:

5x + 3y = - 4

step-by-step explanation:

the equation of a line in standard form is

ax + by = c ( a is a positive integer and b, c are integers )

express the line first of all in slope- intercept form

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

to calculate m use the gradient formula

m = ( y₂ - y₁ ) / ( x₂ - x₁ )

with (x₁, y₁ ) = (7, - 3) and (x₂, y₂ ) = (4, - 8)

m = = -

y = - x + c ← is the partial equation

to find c substitute either of the 2 points into the partial equation

using (4, - 8 ), then

- 8 = - + c ⇒ c = -

y = - x - ← in slope-intercept form

multiply all terms by 3 to eliminate the fractions

3y = - 5x - 4 ( add 5x to both sides )

5x + 3y = - 4 ← in standard form