Answer:
20 seconds
Step-by-step explanation:
speed = distance/time
distance = speed * time
The faster racer will catch up to the slower racer in x meters ahead of the slower racer.
The faster racer is 40 meters behind the slower racer, so he travels x + 40 until he catches up.
Slower racer:
speed = 12 m/s
distance = x
time = t
Faster racer:
speed = 14 m/s
distance = x + 40
time = t (the same time as the slower racer)
Slower racer:
distance = speed * time
x = 12t
Faster racer:
x + 40 = 14t
System of equations:
x = 12t
x + 40 = 14t
Since the fist equation is already solved for x, substitute 12t for x in the second equation and solve for t.
12t + 40 = 14t
40 = 2t
20 = t
t = 20
The faster racer catches up in 20 seconds.
Números que suman 6:
3 + 2 + 1 = 6=> 3^2 + 2^2 + 1^2 = 9 + 4 + 1 = 14
4 + 3 - 1 = 6 => 4^2 + 3^2 + (-1)^2 = 16 + 9 + 1 = 26 => do not use negative numbers, because that will increase the other numbers.
5 + 1 + 0 = 6 => 5^2 + 1 + 0 = 25 + 1 + 0 = 26
4 + 2 + 0 = 4^2 + 2^2 + 0 = 16 + 4 = 20
When you use zero the you increase the sum of the squares.
Then the three numbers that yields the minimum sum of the squares is 1, 2 and 3.
Answer:
x = 8
y = -7
Step-by-step explanation:
This is a system of equations called simultaneous equations. We shall solve it by elimination method Step 1We shall label the equations (1) and (2)−3y−4x=−11.....(1)3y−5x=−61......(2)Step 2Multiply each term in equation (1) by 1 to give equation (3)1(-3y-4x=-11).....(1)-3y-4x=-11....(3)Step 3Multiply each term in equation 2 by -1 to give equation (4)-1(3y−5x=−61)......(2)-3y+5x=61.....(4)Step 4-3y-4x=-11....(3)-3y+5x=61.....(4)Subtract each term in equation (3) from each term in equation (4)-3y-(-3y)+5x-(-4x)=61-(-11)-3y+3y+5x+4x=61+110+9x=729x=72Step 5Divide both sides of the equation by 9, the coefficient of the unknown variable x to find the value of x 9x/9 = 72/9x = 8Step 6Put in x = 8 into equation (2)3y−5x=−61......(2)3y-5(8)=-613y-40=-61Collect like terms by adding 40 to both sides of the equation 3y-40+40=-61+403y=-21Divide both sides by 3, the coefficient of y to find the value of y 3y/3=-21/3y=-7Therefore, the values of x and y that satisfy the equations are 8 and -7 respectively
(n+1)x 2=10
2n+2=10
2n=8
n=4
The original price was 65