Answer:
x=5, y=2
Step-by-step explanation:
You simply write down what you see:
3x - 4y + 4x - 5y = 17
2x - 3y + 3x - 5y = 9
Then you simplify by grouping the x and the y terms:
7x - 9y = 17
5x - 8y = 9
Now you want to get equal amounts of x or y. Let's go for x. If we multiply the top eq with 5 and the bottom one with -7, we get:
35x - 45y = 85
-35x + 56y = -63
-------------------------+ now we can add them:
11y = 22 divide by -11
y = 2
So 7x - 18 = 17, x =5
Finally, it makes sense to double check by filling in these answers in the original equations, just to see if no mistakes were made:
3*5 - 4*2 = 7
4*5 - 5*2 = 10
7+10 = 17: ok!
2*5 - 3*2 = 4
3*5 - 5*2 = 5
4+5 = 9: ok!
Answer:
14.4 m / s
Step-by-step explanation:
=distance between the car
=0.8 × 9
=7.2m
=time taken
=0.5s
=speed
=distance/time
=7.2m/0.5s
=14.4 m / s
Answer:
1999
Step-by-step explanation:
y = 0.2313(y - 1992)^2 + 2.600(y - 1992) + 35.17
verify with known data point
y = 0.2313(2004 - 1992)^2 + 2.600(2004 - 1992) + 35.17
y = 0.2313(12)^2 + 2.600(12) + 35.17
y = 27.9873 + 28.6 + 35.17
y = 99.6772 which verifies our equation
65 = 0.2313x² + 2.6x + 35.17
0 = 0.2313x² + 2.6x - 29.83
quadratic formula
x = (-2.6 ±√(2.6² - 4(0.2313)(-29.83))) / (2(0.2313))
x = (-2.6 + 5.86) / 0.4626 = 7.05 years
7.05 = y - 1992
y = 1999.05
Answer:
5%
Step-by-step explanation:
Lets say 10 add a 0 = 100 9.5 add a 0 = 95.0 (move ok decimal place) so there is a 5% error.
