Answer:
i think it's B correct me if im wrong but it might be A
Step-by-step explanation:
The two numbers that multiply to get 9 and add up to get 10 is 9 and 1.
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
Step-by-step explanation:
1. The midpoint formula says the coordinates of the midpoint are the average of the endpoints.
x = (x₁ + x₂) / 2
y = (y₁ + y₂) / 2
I'll do #2 and #3 as examples.
2. x = (-4 + 10) / 2 = 3
y = (6 + -10) / 2 = -2
So the midpoint is (3, -2).
3. x = (-3 + -6.5) / 2 = -4.75
y = (-8 + -4.5) / 2 = -6.25
So the midpoint is (-4.75, -6.25).