Alex has 84 quarters and nickels worth a total of $17.80.

which equation can be used to find q, the number of quarters alex has?

0.25q + 0.05(q – 84) = 17.80
0.05q + 0.25(84 – q) = 17.80
0.25(q – 84) + 0.05q = 17.80
0.05(84 – q) + 0.25q = 17.80

Equation is used for finding numbers of quarters (q) is 0.05 (84-q) + 0.25q = 17.80 .

Step-by-step explanation:

Let us assume that the number of nickel is represented by n .

Let us assume that the number of quarters is represented by q .

As given

Alex has 84 quarters and nickels worth a total of $17.80.

Than the equation becomes

n + q = 84

As

1 quarters = $ 0.25

1 nickel = $ 0.05

Than the equation becomes

Value of quaters in dollars × q + Value of nickel in dollars × n = Total cost of dollar

0.25q + 0.05n = 17.80

Thus two equations are

n + q = 84

0.25q + 0.05 n = 17.80

(As n + q = 84 thus n = 84 - q)

Putting n = 84 - q in the equation 0.25q + 0.05 n = 17.80.

0.25q + 0.05 (84-q) = 17.80

Therefore the equation is used for finding numbers of quarters (q) is 0.05 (84-q) + 0.25q = 17.80 .

in mathematics, a constraint is a condition of an optimization problem that the solution must satisfy. there are several types of constraints—primarily equality constraints, inequality constraints, and integer constraints. the set of candidate solutions that satisfy all constraints is called the feasible set.

hoped i'm right lol