3x²+x-5=0
a = 3, b = 1, c= -5
-> ∆ ( delta ) = b²-4ac = 61 > 0
-> x1 =( -b+√∆ )÷ 2a =...
x2 = (-b-√∆)÷2a =...
p/s: do your teachers teach you how to use ∆ ( delta ) in maths calculation ? i live in europe and our teachers teach us that way. however, it is a rịght and fast way. you should learn it.
Answer:
20
Step-by-step explanation:
if you divide 50 from 2.5 you get 20
then take 20x2.5 and you get 50.
Answer:
Between 19 and 55, inclusive
Step-by-step explanation:
70 < Average < 79 (inclusive)
4×70 < sum < 4×79 (inclusive)
280 < sum < 316
280 < 92 + 84 + 85 + X < 316
280 < 261 + X < 316
19 < x < 55
Fourth score can be between 19 and 55, inclusive
Answer:
1 : 4
Step-by-step explanation:
Let x represent the amount of 30% solution for 1 unit of 5% solution. Then the amount of acid in the mix is ...
0.30x + 0.05·1 = 0.10·(x +1)
0.30x + 0.05 = 0.10x + 0.10 . . . . eliminate parentheses
0.20x = 0.05 . . . . . . . . . . . . . . . . subtract 0.05+0.10x
x = 0.05/0.20 = 1/4
That is, the ratio x : 1 is 1 : 4.
Answer:
Im not sure but probably its B
