First translate the English phrase "Four times the sum of a number and 15 is at least 120" into a mathematical inequality.
"Four times..." means we're multiplying something by 4.
"... the sum of a number and 15..." means we're adding an unknown and 15 and then multiplying the result by 4.
"... is at least 120" means when we substitute the unknown for a value, in order for that value to be in the solution set, it can only be less than or equal to 120.
So, the resulting inequality is 4(x + 15) ≤ 120.
Simplify the inequality.
4(x + 15) ≤ 120
4x + 60 ≤ 120 <-- Using the distributive property
4x ≤ 60 <-- Subtract both sides by 60
x ≤ 15 <-- Divide both sides by 4
Now that we have the inequality in a simplified form, we can easily see that in order to be in the solution set, the variable x can be no bigger than 15.
In interval notation it would look something like this:
[15, ∞)
In set builder notation it would look something like this:
{x | x ∈ R, x ≤ 15}
It is read as "the set of all x, such that x is a member of the real numbers and x is less than or equal to 15".
if x = 3
3 > -1, and so you use the x² formula.
Plug in 3 for x
x² = (3)²
Simplify
3² = 3 x 3 = 9
9, or (A), is your answer
hope this helps
Ths solubility curve can be used to obtain the amount of salt dissolved (solubility).
<h3>What is the solubility curve?</h3>
The solubility curve is a plot of the solubility of a substance against the temperature. It serves the purpose of being used to show the solubility of a susbtance at different temperatures. This question is incomplete hence we can not be able to deduce the solubility of the salt at this temperature.
If the solubility curve has been ploted, then we can be able to estimate the solubility of the salt from the graph.
Learn more about solubility curve: brainly.com/question/9537462
Step-by-step explanation:
step 1: given= 6*0=0
step 2: Use the distributive property
step 3: Substitute
step 4: -
step 5: Subtract 60 from both sides
step 5: simplify
