BECE Mathematics 2015 Paper

Analyzing the $x$ and its corresponding $y$, you will realize that the $y$ s are obtained by squaring the $x$.Hence $y \rightarrow x^2$You could as well test each of the rules by substituting the value of $x$ into it and see if you will obtain its corresponding $y$.Testing $y \rightarrow x+2$When $x=1, y=1+2=3$The result obtained isn't the value in the mapping. The expected value for $x=1$ is $1$. Hence $y \rightarrow x+2$ is not the rule. Testing $y \rightarrow 2x$When $x=1, y \rightarrow 2 \times 1=2$The result obtained isn't the value in the mapping. The expected value for $x=1$ is 1 . Hence $y \rightarrow 2x$ is not the rule.Testing $y \rightarrow x^2$ When $x=1, y=1^2=1$When $x=2, y=2^2=4$When $x=3, y=3^2=9$When $x=4, y=4^2=16$When $x=5, y=5^2=25$As you can see, $y \rightarrow x^2$ is the rule as each of the substituted $x$ gave its corresponding $y$ value.You can still verify the last rule.Testing $y \rightarrow 2x+2$When $x=1, y=2(1)+2=4$The result obtained isn't the value in the mapping. The expected value for $x=1$ is $1$. Hence $y \rightarrow 2x+2$ is not the rule.