worth *100* points

what number should be added to the expression a" +4a to change it into a pertect square trinomial?
a.2
b.4
c.1
d.8

It should be B.4

Step-by-step explanation:

it is B.4 hope this helps good luck

Step-by-step explanation:

Fundraiser sold 150 caramel candy bars and 75 almond candy bars

Solution:

Let "c" be the number of caramel candy bars sold

Let "a" be the number of almond candy bars sold

Cost of 1 caramel candy bar = $ 0.75

Cost of 1 almond candy bar = $ 1

He sold 225 candy bars. Therefore, we can frame a equation as;

number of caramel candy bars sold + number of almond candy bars sold = 225

c + a = 225 ----- eqn 1

He earned a total of $ 187.50. Therefore, we can frame a equation as;

number of caramel candy bars sold x Cost of 1 caramel candy bar + number of almond candy bars sold x Cost of 1 almond candy bar = 225

0.75c + a = 187.5 --------- eqn 2

Let us solve eqn 1 and eqn 2

From eqn 1,

c = 225 - a ------ eqn 3

Substitute eqn 3 in eqn 2

0.75(225 - a) + a = 187.5

168.75 - 0.75a + a = 187.5

0.25a = 18.75

a = 75

Substitute a = 75 in eqn 3

c = 225 - 75

c = 150

Thus he sold 150 caramel candy bars and 75 almond candy bars