Answer:
100 POINTS!!! PLEASE SHOW YOUR WORK. I WANT TO UNDERSTAND IT
5 QUESTIONS
1) Pedro wants to make a 35% sugar solution. He has 3 ounces of a 56% sugar. How many ounces of a 14% sugar solution must he add to this to create the desired mixture?
2) Xavier wants to make 10 gallons of a 42% saline solution by mixing together a 50% saline solution and a 10% saline solution. How much of each solution must he use?
3) A passenger on a plane made a trip to Portland and back/ The plane took the same route coming back. On the trip there it flew 210 kilometers per hour and on the return trip it went 280 kilometers per hour. If the total trip took 5 hours, how long did the trip take coming back?
4) Amanda and Alexis live 4 miles apart. They decide to start walking toward each other's houses at the same time. Amanda walks at a rate of 3.5 miles per hour and Alexis walks at a rate of 4 miles per hour. How long will it take for them to meet?
5) Working alone, Juan can harvest a field in 13 hours. Shayna can harvest the same field in 14 hours. Find how long it would take them if they worked together.
Total distance traveled = 4 + 6 = 10 miles
Total time = 15 + 25 = 40 minutes
Speed = 10 miles ÷ 40 minutes = 0.25 mph
8p² - 16p = 10
8p² - 16p - 10 = 0 Divide through by 2
4p² - 8p - 5 = 0
Multiply first and last coefficients: 4*-5 = -20
We look for two numbers that multiply to give -20, and add to give -8
Those two numbers are 2 and -10.
Check: 2*-10 = -20 2 + -10 = -8
We replace the middle term of -8p in the quadratic expression with 2p -10p
4p² - 8p - 5 = 0
4p² + 2p - 10p - 5 = 0
2p(2p + 1) - 5(2p + 1) = 0
(2p + 1)(2p - 5) = 0
2p + 1 = 0 or 2p + 5 = 0
2p = 0 -1 2p = 0 - 5
2p = -1 2p = -5
p = -1/2 p = -5/2
The solutions are p = -1/2 or -5/2
Step-by-step explanation:
Sn=n/2(2a+(n-1)d)
910=n/2{2a+(n-1)d}
1820=n{2a+(n-1)d}
1820=20{2a+(20-1)d}
1820=20{2a+19d}
91=2a+19d
An=a+(n-1)d
95=a+(20-1)d
95=a+19d
91=2a+19d
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4=-a
a=-4
91=2a+19d
91=2(-4)+19d
91=-8+19d
91+8=19d
99=19d
d=99/19
A=-4
no it's 22 :D...............
