Answer:
A the first one
Step-by-step explanation:
Answer:
The number 312 lies between the perfect cubes 216 and 343.
So the cube root of 312 lies between the number 6 and 7.
This means that the cube root of 312 is an irrational number because it is not a perfect cube root.
Step-by-step explanation:
You’d set up a proportion. I did 25/15=7x-40/18.
Then you would cross multiply to get 15(7x-40)=450
Distribute the 15.
105x-600=450
Add 600 to both sides, so the -600 cancels out.
Then you’re left with 105x=1050
Divide both sides by 105 and you get x=10
Answer:
the two number are 7 and 9
Step-by-step explanation:
2*x+y=25
3x-y = 20
add the two equations
2*x+y=25
3x-y = 20
---------------
5x = 45
divide by 5
5x/5 = 45/5
x = 9
lets find y
2x+y = 25
substitute x
2*9 +y =25
18+y =25
subtract 18 from both side
y = 25-18
y =7
