A gardener has two fertilisers that contain different concentrations of nitrogen. One is 3% nitrogen and the other is 11% nitrogen. How many pounds of each should she mix to obtain 20 pounds of a 9% concentration? 1. Define the variables if they are not already defined in the problem, i. e. Let x be and y be (10 marks).

2. How many equations do we need to model the problem? Write down the equations in terms of the variables (20 marks)

3. Solve the system of equations by substitution or elimination. Write down the steps clearly (20 marks).

4. Sketch the graph of this system of equations. Indicate the x-intercept and y-intercept of each equation. Also indicate the intersection point (40 marks).

5. Indicate the solution and make a recommendation to the gardener(10 marks).

the bottom of the spinner is not flat.

step-by-step explanation:

da freeck kinda math is this just drop out

step-by-step explanation:

it would take 7/10 of an hour too fill the pool.

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