Help on this question

y = 3

Step-by-step explanation:

PQ(5 - 12;-10 + 2) => PQ(-7;-8)

RS(8; y - 10)

because PQ⊥RS

=> (-7).8 - 8(y - 10) = 0

<=> y - 10 = -7

<=> y = 3

if x decreases by 4 then y increases by 10

step-by-step explanation:

if you are saying purchasing 3 social media ads and one newspaper ad counts as one purchase then there are:

6 purchases

if you are asking how many of each then:

18 social media ads

6 newspaper ads