Let a, b and c be sets.
(a) suppose that a ⊆ b and b ⊆ c. does this mean that a ⊆ c? prove your answer. hint: to prove that a ⊆ c you must prove the implication, “for all x, if x ∈ a then x ∈ c.”
(b) suppose that a ∈ b and b ∈ c. does this mean that a ∈ c? give an example to prove that this does not always happen (and explain why your example works). you should be able to give an example where |a| = |b| = |c| = 2.

the answer to the expression is 83

5x + 3y = - 4

step-by-step explanation:

the equation of a line in standard form is

ax + by = c ( a is a positive integer and b, c are integers )

express the line first of all in slope- intercept form

y = mx + c ( m is the slope and c the y-intercept )

to calculate m use the gradient formula

m = ( y₂ - y₁ ) / ( x₂ - x₁ )

with (x₁, y₁ ) = (7, - 3) and (x₂, y₂ ) = (4, - 8)

m = = -

y = - x + c ← is the partial equation

to find c substitute either of the 2 points into the partial equation

using (4, - 8 ), then

- 8 = - + c ⇒ c = -

y = - x - ← in slope-intercept form

multiply all terms by 3 to eliminate the fractions

3y = - 5x - 4 ( add 5x to both sides )

5x + 3y = - 4 ← in standard form

answer: the answer is b. i think hope i got it correct

step-by-step explanation: