If set a = {3, 4, 7, 9}, set b = {8, 9, 10, 11}, and set c = {4, 9, 11, 13, 15}, then a∩(b∪c) =

{}
{4, 9}
{3, 4, 7, 9, 11}

A = {3, 4, 7, 9}

B = {8, 9, 10, 11}

C = {4, 9, 11, 13, 15}

A∩(B∪C)

First let's solve parentheses, we want the union between B and C.

B∪C = {4, 8, 9, 10, 11, 13, 15}

Now we want the interception between A and this, which means we want just the value which appears in both.

A∩{4, 8, 9, 10, 11, 13, 15} = {4, 9}

-3

step-by-step explanation:

a drawing really does here:

so i draw the horizontal line y=2 and the vertical line x=-2 at this intersection i put b (this is where my right angle is going to be).   so point b is at (-2,2).   point a is 5 units long and is also on y=2 so this point has to be (3,2) or (-7,2) -doesn't matter i will go with (3,2).

now we know c is at (-2,y) we don't know the y yet bet we know that c is on x=-2.

we have the area of the triangle is .5bh=12.5

we know the base length is 5 (ab)

we have the height is (2-y) if you look at your

plug in

.5(5)(2-y)=12.5

solve for y to get the y-coordinate for c

2.5(2-y)=12.5

divide both sides by 2.5 giving:

2-y=5

now subtract 2 on both sides

-y=3

y=-3