Answer:
Is it a multiple choice question
Step-by-step explanation:
All together: <span>3x + 0.05 + x + x + 0.10 = 7.50
5x + 0.15 = 7.50
5x = 7.35
x = 1.47
</span>1.47 +0.10=1.57<span>
so, the drink costs 1.57 </span>
Answer:
y = 2
Step-by-step explanation:
use slope formula:
(4 - y) / (3 - 10) = -2/7
4-y / -7 = -2 /7
cross-multiply:
7(4 - y) = (-7)(-2)
28 - 7y = 14
-7y = -14
y = 2
The trick here is to relate the NUMBER of coins to each other in one equation, and then the VALUE of the coins in another equation. If I have 1 dime, that 1 dime is worth 10 cents. The number of dimes is obviously not equal to the value. Let's call quarters q and dimes d. The number of these 2 types of coins added together is 80 coins. So q + d = 80. Now, we know that quarters are worth .25 and dimes are worth .1, so we express a quarter's worth as .25q; we express a dime's worth as .1d. The value of the coins we have is 14.90. So that equation is .25q + .1d = 14.90. Let's solve the first equation for q. q = 80 - d. We can now use that as a substitution for q into the second equation, giving us an equation with only 1 unknown, d. .25(80-d) + .1d = 14.90. Distributing through the parenthesis we have 20 - .25d + .1d = 14.90. Combining like terms gives us - .15d = - 5.1. We will divide both sides by - .15 to get that the number of dimes is 34. If we had a total of 80 coins, then the number of quarters is 80 - 34, which is 46. 46 quarters and 34 dimes
