Y = 6x
4x + y = 7
(substitute y = 6x in the ‘y’ spot in 4x + y = 7)
4x + 6x = 7
10x = 7
/10 on both sides
x = 7/10
(substitute x = 7/10 in the ‘x’ spot in either of the two equations)
y = 6x
y = 6(7/10)
y = 4.2 = 21/5
Answer:
x = 7/10
y = 21/5
The answer is 1,000. 500(2)= 1000
Uh... 3 1/2 jail? I don't know.
Ok this inequality tells you the number of devices you can have before the new plan costs more than the old plan. The new plan expression is $4.50x + $94m = y ( total cost). The old plan is $175m = y (total cost). You can see m (number of months) in both equations, you don't need it this time since we're going to to compare both to one month. Since they're both equal to y you can make them equal to each other. $4.50x + $94 = $175. Now you want to figure when the new plan is less than the old plan you switch the equal sign for a less than sign. $4.50x + $94 < $175; this will help you find the inequality you want. From there just use algebraic steps to find that x has to less than 18 or
x < 18.
1) When the denominator equals zero that is a critical point
=> x - 2 = 0 => x = 2.
So x = 2 is a critical point
2) Simplify the numerator to find an expresion of the king p(x) ≥ 0 or p(x) ≤ 0. Where p(x) equals zero you have other(s) critical point(s)
Multiply both terms:
[2x + 5] / [ x - 2] = [x - 1] / [x - 2]
for x ≠ 2 => 2x + 5 = x - 1
=> 2x - x = - 1 - 5
=> x = - 6
Then, the two critical points are x = 2 and x = - 6.
Answer: option B.
