Answer: x ≥ 17
Step-by-step explanation:
We know that she worked 7 hours at a dinner, for $10 per hour last week.
Then in the last week, she did make:
7*$10 = $70
Now she babysits, she wins $8 per hour, then if she works x hours, she will win:
w(x) = $8*x
if we add the $70 that she already had, we have:
$70 + $8*x
And we know that she wants to have, at least, $206, then we can write the inequality.
$70 + $8*x ≥ $206.
Now let's solve this for x.
first, we can subtract $70 in both sides:
($70 + $8*x) - $70 ≥ $206 - $70
$8*x ≥ $136
now we can divide by $8 in both sides:
($8*x)/$8 ≥ $136/$8
x ≥ 17
This means that she must babysit for at least 17 hours if she wants to buy the dress.