A sports marketing company interviewed 250 Supersport United fans and has found that the average fan spends R101 on non-ticket purchases at the stadium when he/she attends a home match. This includes money spent on food, drinks and merchandise. Assume that the standard deviation is R39. Find the lower and upper limits for the average amount spent on non-ticket purchases per match by Supersport United fans. Use a confidence level of 90%. Round off your answers to 2 decimal places (4)

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

answer: c

(2, -4)

goes 7 to the

(9, 4)

easy