If y is directly proportional to x and y = 5 when x = 2, find the value of y when
x=7.

y = 17.5

Step-by-step explanation:

Given y is directly proportional to x then the equation relating them is

y = kx ← k is the constant of proportion

To find k use the condition y = 5 when x = 2, thus

5 = 2k ( divide both sides by 2 )

2.5 = k

y = 2.5x ← equation of proportion

When x = 7, then

y = 2.5 × 7 = 17.5

answer: on graphs, the open and closed circles, or vertical asymptotes drawn as dashed lines us identify discontinuities.

as before, graphs and tables allow us to estimate at best.

when working with formulas, getting zero in the denominator indicates a point of discontinuity.

when working with piecewise-defined functions, check for discontinuities at the transition points where one piece ends and the next begins.

step-by-step explanation: