Let the time = X
Distance = Rate times time
Level roads = 18x
Hills = 10x
Total is 98 miles
18x+10x = 98
Add:
28x = 98
Divide both sides by 28:
x = 3.5
She spent 3.5 hours on each part
Total time = 3.5 + 3.5 = 7 hours
Answer:
x, x+2, x+4
(x+2)^2 - 4(x) = 6(x + 4) + 7
x^2 + 4x + 4 - 4x = 6x + 24 + 7
x^2 - 6x - 27 = 0
x = 9 (∨ x = -3)
The three numbers are
9, 11, 13
but it could be also
-3, -1, 1
Answer:
76, 11.2, 11
Step-by-step explanation:
1. (82+72+45+91+58+83+65+87+90+77+73+89)/12= 912/12 = 76
2. (6+4+31+15+18+7+11+11+14+1+3+13)/12= 134/12= 11.2
3. 11 students
Answer:
reflection from the x-axis
5x + 2y = 13
x + 2y = 9
Subtract :- ( note that 2y - 2y = 0):-
4x + 0 = 4
x = 1
From 2nd equation plug in x = 1
1 + 2y = 9
2y = 8
y = 4
Solution to this equation is x=1,y=4
2x + y = 7
5x - y = 14
Adding eliminates the y terms because y + -y = 0 :-
7x + 0 = 21
7x = 21
x = 3
Plug x=3 into second equation:-
5(3) - y = 14
y = 15-14 = 1
solution is x =3, y = 1