The answer to this question is= 13
Answer:
x=2 and y= -3
Step-by-step explanation:
This is a simultaneous equation. To solve this type of equation, there are three methods; substitution, Elimination and Graphical.
But here, we would be using the substitution method.
3x-y=9 Equation 1
2x-y=7. Equation 2
Getting y from equation 2, we have
-y= 7-2x
Multiply both sides by -
y= 2x-7 Equation 3
Substituting y for 2x-7 in equation 1, we have
3x- (2x-7)=9
3x-2x+7=9
x+7=9
x=9-7
x=2
Substituting x as 2 in equation 3
y=2x-7
y= 2(2)-7
y= 4-7
y= -3
There are 6C3 = 20 such combinations.
abc, abd, abe, abf
acd, ace, acf, ade
adf, aef, bcd, bce
bcf, bde, bdf, bef
cde, cdf, cef, def
Answer:
It would take her 11 hours
Hope this is right
Step-by-step explanation:
