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
Answer:
A man borrows * 8000
He agrees to repay with a total interest of 1360 in 12 monthly instalments.
Each instalment being less than the preceding one by * 40
= x 40
= 12 x 34
= 408 (Ans)
Answer:
Yumiko should multiply the other equation by 3.
If she adds the two equations she would be left with the variable 'x'.
Step-by-step explanation:
Given the two equations are as follows:
It is given that she multiplies the first equation by 6. Therefore, (1) becomes
Now, note that the sign of the variable 'y' is negative. So, if we make the co-effecient of 'y' equal in both the cases, add them it would result in the elimination of the variable 'y'.
The co-effecient of y in Equation (2) is 6. To make it 18 like it is in Equation (1), we multiply throughout by 3.
Therefore, Equation (2) becomes:
Now, we add Equation (a) and Equation (b).
Factor: 3
Equation: 27x = 126