Question

Solve the compound inequality. Write the solution set using interval notation.
-7x < -21 and x + 7 >8
a) (1, infinity)
b) (3, infinity)
c) (1,3)
d) no solution

Answer 1

-7x < -21
7x > 21
x > 3

x + 7 > 8
x > 1

Answer 2

Since both are going the same way,
so it's a.

Answer 3

i thought it would be c?

Answer 4

oh nvm, now i get it.

Answer 5

this is an "and" statement so it has to satisfy x>3 AND x>1. it's the intersection of the solution sets. so it's b.

Answer 6

@dpaInc , isn't it A?

Answer 7

hi saif... the question says "and" so it has to satisfy both sets.. x>3 and x>1. if x=2, does it satisfy both x>3 AND x>1?

Answer 8

Hii. :D
Oh wow.. that's a perfect point.