Answer:
"differential selection"
Step-by-step explanation:
If your friend took the test twice and passed both times with a score above 90% then the minor difference in price is most likely due to "differential selection". The first test had questions that he had a little more experience in solving, while the second time he was most likely given a couple questions that he wasn't as prepared for as he was the first time. This is most likely the cause for the difference in percentiles.
I hope this answered your question. If you have any more questions feel free to ask away at Brainly.
Step-by-step explanation:
a.
simply add both equations
x + y = 2
-3x - y = 5
----------------
-2x + 0 = 7
x = -7/2
x + y = 2
-7/2 + y = 2
y = 2 + 7/2 = 4/2 + 7/2 = 11/2
b.
1/2 x + 2y = -13
x - 4y = 8
first multiply the first equating by 2
x + 4y = -26
x - 4y = 8
--------------------
2x + 0 = -18
x = -18/2 = -9
x - 4y = 8
-9 - 4y = 8
-4y = 17
y = -17/4
At least 15 b/c is you add QWERTY to -12, you get zero and adding 5 to get 15 in total.
First set everything to 0.
Giving you A= 1 , B= 1 and C= -5
Then input everything into the quadratic formula and either solve by hand or use a calculator.
Note exact values are found by hand, decimals are found using a calculator.
