Answer:
75 general
105 student ID
Step-by-step explanation:
(it's a system)
4x+3y=615
x+y=180
(system as well)
4x+3y=615
x=180-y
4(180-y)+3y=615
720-4y+3y=615
-y=-105
y=105
x+105=180
x=180-105
x=75
The relation t is one-to-one, so it is a function and so is its inverse
Answer:
The solution of the inequation
is
.
Step-by-step explanation:
First of all, let simplify and factorize the resulting polynomial:



Roots are found by Quadratic Formula:
![r_{1,2} = \frac{\left[-\left(-\frac{11}{6}\right)\pm \sqrt{\left(-\frac{11}{6} \right)^{2}-4\cdot (1)\cdot \left(-\frac{10}{6} \right)} \right]}{2\cdot (1)}](https://tex.z-dn.net/?f=r_%7B1%2C2%7D%20%3D%20%5Cfrac%7B%5Cleft%5B-%5Cleft%28-%5Cfrac%7B11%7D%7B6%7D%5Cright%29%5Cpm%20%5Csqrt%7B%5Cleft%28-%5Cfrac%7B11%7D%7B6%7D%20%5Cright%29%5E%7B2%7D-4%5Ccdot%20%281%29%5Ccdot%20%5Cleft%28-%5Cfrac%7B10%7D%7B6%7D%20%5Cright%29%7D%20%5Cright%5D%7D%7B2%5Ccdot%20%281%29%7D)
and 
Then, the factorized form of the inequation is:

By Real Algebra, there are two condition that fulfill the inequation:
a) 


b) 


The solution of the inequation
is
.
The answer is the last one (absolute value)