Let's say that number is hmmm "a"
now.. twice "a" is 2*a or 2a
4 less than that is " 2a - 4"
now, the product of those two fellows is 286, well ok
a( 2a - 4) = 286
thus
As the variation is direct we have:

We must find the value of k.
For this, we use the following data:
y = 200 when x = 5
Substituting values we have:

Clearing k:

Then, the function is:

We evaluate the function for x = -3
Answer:
the value of y when x = -3 is:
c.
72
Answer:
Step-by-step explanation:
Isn’t this mathematics not science
Answer:
x=15
Step-by-step explanation:
Step 1: Multiply both sides by 2.
Step 2: Simplify both sides of the equation.
6x+18=108
Step 3: Subtract 18 from both sides.
6x+18−18=108−18
6x=90
Step 4: Divide both sides by 6.
x=15
Answer:
12 cm
Step-by-step explanation:
To calculate the length of a spring with a 2 kg load, compare the displacement of a 1 kg load and adjust accordingly.
When a 1 kg load is suspended from the spring, the spring which is 6 cm stretches to 9 cm. This is 3 cm longer due to the weight. If you attach a weight which is twice as much then the displacement will be twice as much. Instead of stretching an additional 3 cm, it will stretch 2*3 = 6 cm. Add this to the length of the spring and it stretches in total 6 + 6 = 12 cm.