Question

Choose the mapping diagram that represents the function given below.

$y=2x+3,$ where $x\in \{1,2,3\}$

• A.
• B.
• C.
• D.

Answer 1

The correct option is C

The given function is $y=2x+3.$

Let us find the values of $y$ when $x=1,2,\text{and}3.$

$x=1⟹y=2\left(1\right)+3=2+3=5$

$x=2⟹y=2\left(2\right)+3=4+3=7$

$x=3⟹y=2\left(3\right)+3=6+3=9$

$\therefore$ We can express the function as the set of ordered pairs $(1,5),(2,7),(3,9).$

$\therefore$The mapping diagram that represents this function is: