1/10x + 6 = 2/5x
6 = 2/5x - 1/10x
6 = 4/10x - 1/10x
6 = 3/10x
6 / (3/10) = x
6 * 10/3 = x
60/3 = x
20 = x <=== the gas tank can hold 20 gallons
Use pythagorena theorme
D=

NOTE: x1 and x2 means the first x and second x, not x^1 and x^2
points given are
(1,1)
(5,6)
x1=1
y1=1
x2=5
y2=6
D=

D=

D=

D=

6.403
answer is B
Reduce each ratio to its minimum expression to find if they are equal.
35:28

10:8

Since both ratios reduce to 5:4, they are equivalent.
Another way to check a:b is equivalent to c:d, is that a*d = b*c
In this case, this will be true if 35 times 8 is equal to 10 times 28:

Since both products are equal, then the ratios are equivalent.
B. x^2 + 5x - 4 = 0
Anyway that you try to factor it will not work
~~hope this helps~~
D = 390mi
r = 60 mi/h
390/60 = 6.5
(t) = 6.5 h