Answer:
(- 2, 3 )
Step-by-step explanation:
Given the 2 equations
x + y = 1 → (1)
2y - x = 8 → (2)
Adding the 2 equations term by term will eliminate the x- term
(x - x) + (y + 2y) = (1 + 8), that is
3y = 9 ( divide both sides by 3 )
y = 3
Substitute y = 3 into either of the 2 equations and solve for y
Substituting y = 3 in (1)
x + 3 = 1 ( subtract 3 from both sides )
x = - 2
Solution is (- 2, 3 )
Answer:
Option B
Step-by-step explanation:
When moving with the current, the speeds of the boat and current will add up. The first situation can then be represented by:
9 = 0.5(x + y)
While opposing the current, the speeds will be subtracted. Forming:
9 = 1.5(x - y)
The second option contains this equation system, so it is correct.
To get the time taken for Jan and Jo to meet we proceed as follows;
Jan's speed=70 mph
Jo's speed =60 mph
distance between =1170
relative speed=70+60=130
time taken for them to meet will be:
time=(distance)/(relative speed)
=1170/130
=9 hours
the answer is 9 hours
