Answer:
Let the matrix associated to the system and
the vector of constant values of the system.
The equation of the line joining p and q is
. Since p and q are solutions of the linear system then, and
Let . Observe that . Then w is a solution of the homogeneous system Ax=0.
Now, let s=p+r(q-p) for some be a point in the line joining p and q. Observe that
Then As=b. This means that s is a solution of the linear system.
B 5 makes the most sense to me
The answer is C.
Note when Soro divides both sides by -2.5 to solve the equation. When multiplying/dividing by a negative number, one should always reverse the inequality sign, but Soro forgot to do this.
-2.5x≥-30
After this step, the answer SHOULD HAVE been:
x≤12
Let me know if you need any clarifications, thanks!
X+y=77.95
x-y=30.61
x+x+y-y=108.56
2x=108.56 (divide by 2 both sides of the equation)
x=54.2
y=77.95-x=77.95-54.2=23.67
y=23.67
answer: they are 54.2 and 23.67