Answer:
Amy has 12 5¢ coins
Step-by-step explanation:
Let <em>x</em> represent 20¢ coins and <em>y</em> represent 5¢ coins.
Amy has four more 20¢ coins than 5¢ coins. Hence:

And the total value of all her coins is $3.80. Thus:

This yields a system of equations:

We can solve by substitution. Substitute the first equation into the first:

Distribute:

Combine like terms:

And divide both sides by 0.25. Hence:

Thus, Amy has 12 5¢ coins.
Using the first equation:

Substitute:

Thus, Amy has 16 20¢ coins.
In conclusion, Amy has 12 5¢ coins and 16 20¢ coins.
Answer:
c
Step-by-step explanation:
A.) weight/(height x height)x 703
Answer:
D it
Step-by-step explanation:
We have two equations, A quadratic and a linear equation.
The domain of a linear equation and quadratic equation is all real numbers but since it dealing with time we must make sure the roots or x-intercepts is positive.
Looking at the quadratic equation, we can use the discramnt formula to see if all roots are positve.



The discramnt is greater than zero so there is two distinct real roots. So let check if they are positve
If you graph the equation, it intercepts at two positve roots so it is D
Answer:
The length of TQ is 14.
Step-by-step explanation:
The length of SV and VS are the same.
4x - 1 = 15
4x = 16
x = 4
Similarly, the length of TS and TQ are the same.
3x + 2 = 3(4) + 12 = 14