X=3 and the work to get the answer is attached.
Answer:
I think ti is 15 i fi am wrong I am sorry
Area=1/2 times base times height
area=60
height=12
60=1/2 times base times 12
divide both sides by 12
5=1/2 times base
multipy both side sby 2
10=base
10 units=base
<h2>Answer:</h2>
A prism is a solid object having two identical bases, hence the same cross section along the length. This is a rectangular prism its base is a rectangle. multiplying the three dimensions of a rectangular prism: length, width and height, gives us the volume of a prism:

Therefore, Associative Property can be used to mentally find the volume of the prisms shown by selecting the easier way of the multiplication. For instance, we can say that:

In whose case:

To operate this mentally is not an easy way, but<em> what if we rotate this shape? </em>so we say that:

Then, the volume can be found as:

There are two forms of finding the result. First, multiplying 18 by 20 and then the result by 5, but as in the previous case this is a tricky way to do mentally:

Hence, here we can use Associative Property multiplying 20 by 5 and then the result by 18:

This last arrangement is easier because 20 x 5 is easy to remember given that the result is 100. Then, by multiplying this result by 18 then we get 1800.
Answer: The missing angle is 13°
Step-by-step explanation:
Let ∠B
be the missing angle.
Let ∠A
be the angle that measures
77∘Let ∠C
the right angle that measures
90∘
The following is true of all triangles:
∠A+∠B+∠C=180∘
Express the above equation as
∠B
in terms of the other angles:
∠B=180∘−∠A−∠C
Substitute the values for ∠A and ∠C
∠B=180∘−77∘−90∘
∠B=13∘