Answer:
Total number of points in the test = 100
Total number of items in the test = 40
Let number of items of 2 points be x and number of items of 3 points be y.
Now, using the given information the situation can be represented by using the following equations :
⇒ x + y = 40 .........(1)
⇒ 2x + 3y = 100 .........(2)
The matrix equation is :
By solving the equation (1) and equation (2), we get :
Solution : x = 20 and y = 20
If you need to solve this equation you can multiply the both side of equation on (-1). Like that
<span>2 = (-x);
-1·2 = (-1)·(-x)
if you multiply negative and </span><span>positive </span>you'll have negative,
if you multiply negative and <span>negative you'll have </span><span><span>positive. So
</span>
</span>-2 = x. or
x = -2.
The answer is -2.
<span>Combinations. This is because in combinations the order does not matter
</span>
3, 7×3=21+5=26, there is your answer
