Try x = 65
Look at my image
Answer:
5.15
Step-by-step explanation:
17.51 / 3.4 = 5.15
Answer: the system has no solution.
Step-by-step explanation:
\displaystyle\\
\left \{ {{x^2y=16\ \ \ \ \ (1)} \atop {x^2+4y+16=0\ \ \ \ \ (2)}} \right. .\\
Multiply\ both\ sides\ of\ the\ equation\ (2)\ by\ y\ (y\neq 0):\\
x^2y+4y^2+16y=0\\
We\ substitute\ equation\ (1)\ into\ equation\ (2):\\
16+4y^2+16y=0\\
4y^2+16y+16=0\\
4*(y^2+4y+4)=0\\
4*(y^2+2*y*2+2^2)=0\\
4*(y+2)^2=0\\
Divide\ both\ sides\ of\ the \ equation\ by\ 4:\\
(y+2)^2=0\\
(y+2)*(y+2)=0\\
So,\ y+2=0\\
y=-2.\\
Ok, so the starting numbers are the fixed amounts. If we think of a graph, this is the y-intercept/ starting point and the rate would continue from there. This conclusion is very important to writing a linear equation in slope-intercept form.
If you don’t remember, slope-intercept form is y=mx+b, where m is the slope and b is the y-intercept.
First, let’s make our equations.....
Plan A: y = 0.07x + 26
Plan B: y = 0.12x + 17
Now since it is not stated, I’m not sure if you need to find where the cost of both plans is equal, but that would be found by setting up a system of equations and using substitution.
y = 0.07x + 26
y = 0.12x + 17
Substitute one equation into the other...
0.07x + 26 = 0.12x + 17
- 0.05x = -9
0.05x = 9
x = 180
And there you have it! After 180 minutes [3 hours] of talking, both phone plans will have the same cost.
(21 * 1.10) / 3 = 23.10/3 = 7.7....so each friend has to pay $ 7.70
