B. 4/5
C. 2/9
D. 4/9
actually 0.00444444444 as a fraction
3x+2y= 9
14x + 10y = 14
Answer:
2 or 4
Step-by-step explanation:
Answer:
1. 3 2/3
2. 4 9/10
3. 1 27/56
4. 58 2/15
5. 11 1/24
Step-by-step explanation:
1. To find the answer, add 3 1/6 and 5 9/10. First change them into improper fractions. 5 9/10 is 59/10 and 3 1/6 is 19/6. Now, you have to make the denominator (bottom number) the same number for both fractions. To do this you must find a LCM for both the number (10, 6) a LCM for these numbers is 30. Now to change the denominator to this you must times the numerator and denominator by the number needed to get the LCM for the denominator.
So 6 x 5 = 30 and 3 x 10 = 30.
19/6 x 5 = 95/30 and 59/10 x 3 = 177/30
Now add the fractions:
This equals 272/30
Simplify:
Now take 12 5/6 and turn it into a improper fraction: 77/6
Now again, you have to make the denominator to 30
77/6 x 5 = 385/30
Now subtract 385/30 - 272/30
This equals 113/30
Now turn this back into a mixed fraction:
3 23/30
The answer is 3 23/30
This process is basically the same for all the other questions.
Answer:
y = -1.2x² +6.6x +2
Step-by-step explanation:
The quadratic regression function of a calculator or spreadsheet can do this for you. The resulting function is ...
y = -1.2x² +6.6x +2
_____
If you want to do this by hand, put the given (x, y) values into the formula ...
ax² +bx +c = y
and solve the resulting system of equations.
The third point tells you c=2, so you can simplify the system of equations to ...
a(-2)² +b(-2) +2 = -16 ⇒ 4a -2b = -18 ⇒ 2a -b = -9
a(3)² +b(3) +2 = 11 ⇒ 9a +3b = 9 ⇒ 3a +b = 3
Adding these equations together gives ...
(2a -b) +(3a +b) = (-9) +(3)
5a = -6 . . . . . . . . simplify
a = -1.2 . . . . . . . divide by 5
b = 3 -3a = 3 -3(-1.2) = 6.6 . . . . from the second equation
Now we know the coefficients are a=-1.2, b=6.6, c=2, so the function is ...
y = -1.2x² +6.6x +2