Answer:
30 mph
Step-by-step explanation:
time = distance/speed
If x represents Jane's speed along the summit then her total exploration time is ...
12/x + 40/(x -5) = 2 . . . . . hours
Multiplying by (x)(x -5), we get ...
12(x -5) +40(x) = 2(x)(x -5)
Dividing by 2 and subtracting the left side gives ...
x^2 -31x +30 = 0
(x -30)(x -1) = 0 . . . . . factor
Solutions are x = 30 and x = 1, values of x that make the factors zero. A speed of 1 mph makes no sense in this problem, so ...
Jane's speed along the summit was 30 mph.
Answer:
Step-by-step explanation: explique melhor
Yes it is less than 4,862
Answer:
Step-by-step explanation:
Answer:
x = -3
y = 8
Step-by-step explanation:
x + 2y = 13 ------------(I)
x = 13 - 2y -----------(II)
-2x - 3y = -18 ----------(III)
Substitute x = 13 - 2y in equation (III)
-2*(13 - 2y) - 3y = -18
-2*13 - 2y *(-2) -3y = -18
-26 + 4y - 3y = -18 {Combine like terms}
-26 + y = -18 {Add 26 to both sides}
y = -18 + 26
y = 8
Substitute y = 8 in equation (II)
x = 13 - 2*8
= 13 - 16
x = -3
x = -3
y = 8
