Ch.3 Equations & inequalities

Question 1

how can linear simultaneous equations be solved?

Answer 1

either elimination or substitution

Question 2

what is the solution of an inequality?

Answer 2

the set of real numbers that make the inequality true

Question 3

using set notations how would you write when x is greater than 2.75?

Answer 3

{x:x>2.75}

Question 4

in set notation what are the two ways that x > -2 and x < 4?

Answer 4

{x: -2 < x < 4}

{x: x > -2} ∩ {x: x < 4}

Question 5

in set notation how would you write if x < -1 or x > 3?

Answer 5

{x: x < -1} ∪ {x: x > 3}

Question 6

if two sets of values overlap ( intersect ) where -2 < x < 6.5 how would you write it in set notation?

Answer 6

{x: -2 < x < 6.5}

Question 7

if there is no overlap between the two sets of values when x < 2 and x > 3 how would you write it in set notation?

Answer 7

{x: x < 2} ∪ {x: x > 3}