Answer:
x=-6
Step-by-step explanation:
2x+y=-4
5x+3y=-6
solve :
multiply first equation by 3
6x+3y=-12
5x+3y=-6
subtract the two equations : 6x+3y-5x-3y=-12-(-6)
x=-12+6
x=-6
If the larger angle is x and the smaller angle is y, y=(1/2)x+30 since it's 30 more than 1/2 of it. In addition, x+y=180 since they are supplementary. Plugging y=(1/2)x+30 into that, we get x+x/2+30=180=1.5x+30. Subtracting 30 from both sides, we get 1.5x=150. Next, we can divide both sides by 1.5 to get x=100 and y=(1/2)*100+30=50+30=80
Given A = {a, e, i, o, u} and B = {a, l, g, e, b, r}, find A ∪ B.
harkovskaia [24]
Ahh..this is sets topics - A U B = all the elements found in A and B. But do note, do not repeat the elements if it is the same. And if the question were to ask : n(AUB) = total number of elements found in A and B.
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".
