\begin{gathered}\{\begin{array}{ccc}3x+5y=2&|\cdot(-3)\\9x+11y=14\end{array}\\\underline{+\{\begin{array}{ccc}-9x-15y=-6\\9x+11y=14\end{array}}\ \ |\text{add both sides of equations}\\.\ \ \ \ \ -4y=8\ \ \ |:(=4)\\.\ \ \ \ \ y=-2\\\\\text{substitute the value of y to the first equation}\\\\3x+5\cdot(-2)=2\\3x-10=2\ \ \ |+10\\3x=12\ \ \ |:3\\x=4\\\\Answer:\ x=4;\ y=-2\to(4;\ -2)\end{gathered}
{
3x+5y=2
9x+11y=14
∣⋅(−3)
−9x−15y=−6
9x+11y=14
add both sides of equations
. −4y=8 ∣:(=4)
. y=−2
substitute the value of y to the first equation
3x+5⋅(−2)=2
3x−10=2 ∣+10
3x=12 ∣:3
x=4
Answer: x=4; y=−2→(4; −2)
The square root of 16 is 4
Answer: b) -0.625
<u>Step-by-step explanation:</u>
The formula for the z-score is:

Answer: A) 1260
Step-by-step explanation:
We know that the number of combinations of n things taking r at a time is given by :-

Given : Total multiple-choice questions = 9
Total open-ended problems=6
If an examine must answer 6 of the multiple-choice questions and 4 of the open-ended problems ,
No. of ways to answer 6 multiple-choice questions
= 
No. of ways to answer 4 open-ended problems
= 
Then by using the Fundamental principal of counting the number of ways can the questions and problems be chosen = No. of ways to answer 6 multiple-choice questions x No. of ways to answer 4 open-ended problems
= 
Hence, the correct answer is option A) 1260