(a) Answer: One solution.
Explanation: two lines that have same slope with opposite sign will necessarily cross each other at a single point, as one is "pointing uphill" and the other "downhill."
(b) Answer: Infinitely many solutions.
Explanation:
2x + 3y = 5.5
4x + 6y = 11 | divide by 2
-->
2x + 3y = 5.5
2x + 3y = 5.5
--> equations are identical.
2x + 3y = 2x + 3y
so any (x,y) will satisfy this equation. This means infinitely many solutions.
(c) Answer: One solution
Explanation:
Continuing the two lines it becomes obvious they will cross at one point (the solution)
(d) Answer: No solution
Explanation: If the two lines are parallel, they will never cross (by definition of "parallel"). Therefore there will be no solution to the corresponding linear system.
Answer:
The number is -100, Jill can think of something else, now.
Step-by-step explanation:
x = the number
x/4 - 20 = -45 {twenty less than one-fourth of the number is -45}
x/4 = -25 {added 20 to each side}
x = -100 {multiplied each side by 4}
Answer:
What fractional part of a pie will each get
each will get 1/8
If you start with a 12x16 rectangle and cut square with side length x, when you bend the sides you'll have an inner rectangle with sides 
and 
, and a height of x.
So, the volume will be given by the product of the dimensions, i.e.
The derivative of this function is
and it equals zero if and only if
If we evaluate the volume function at these points, we have
So, the maximum volume is given if you cut a square with side length
