9514 1404 393
Answer:
x = 7
Step-by-step explanation:
Using Cramer's rule, the value of x is ...
x = ((2)(-2) -(22)(3))/((-1)(-2) -(4)(3)) = (-4-66)/(2-12) = -70/-10
x = 7
Answer:
speed of motorcycle = 40 mph
speed of car = 50 mph
Step-by-step explanation:
Here is the complete question
A car and a motorcycle leave at noon from the same location, heading in the same direction. The average speed of the car is 30 mph slower than twice the speed of the motorcycle. In two hours, the car is 20 miles ahead of the motorcycle. Find the speed of both the car and the motorcycle, in miles per hour.
Speed = distance / time
This question would be solved using simultaneous equation
let m = average speed of the motorcycle
c = average speed of the car
c = 2m - 30 equation 1
20 =(c - m) x 2 equation 2
insert equation 1 into equation 2 and divide through by 2
10 = (2m - 30) - m
solve for m
m = 40 mph
substitute for m in equation 1
2(40) - 20 = 50 mph
Answer:
It is shifted c units to the left .
Step-by-step explanation:
In general, adding a constant c to the value of x shifts a graph c units to the left.
The graph of y = x + c is parallel to y = x, the y-intercept becomes (0, c) and the x-intercept becomes (-c, 0).
In the diagram below, the red line is the graph of y = x, and the blue line is the graph of y = x + 1.
Answer:
41 and 77
Step-by-step explanation:
x: his age the first time he went to space
y: his age the second time he went to space
the second time he went to space he was 5 years younger than twice the age when he went his first time, then:
y = 2x - 5
the sum of both ages is 118, then:
x + y = 118
If you replace y = 2x - 5 in x + y =118:
x + 2x - 5 = 118
3x = 123
x = 41
replacing x:
41 + y = 118
y = 118 - 41
y = 77
so when he was 77, he was 5 years younger than twice 41 ( 41*2 = 82 => 82 - 5 =77)