Which of the following is the graph of \(y=-3x-3\)?
A. | B. | ||
C. | D. |
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Which of the following is the graph of \(y=-3x-3\)?
A. | B. | ||
C. | D. |
\(A\)
\(y=-3x-3\)
\(\text{By elimination:}\)
\(\ y\text{-intercept}=-3\)
\(\rightarrow\ \text{Cannot be}\ B\ \text{or}\ D\)
\(\text{Gradient}=-3\)
\(\rightarrow\ \text{Cannot be}\ C\)
\(\Rightarrow A\)
Which equation represents the relationship between \(x\) and \(y\) in this table?
\begin{array} {|c|c|c|}
\hline \ \ x\ \ & \ \ 0\ \ &\ \ 2\ \ & \ \ 4\ \ & \ \ 6\ \ & \ \ 8\ \ \\
\hline y & 3 & 4 & 5 & 6 & 7 \\
\hline \end{array}
\(B\)
\(\text{By elimination (using the table)}\)
\((0, 3)\ \text{must satisfy}\)
\(\therefore\ \text{NOT}\ C\ \text{or}\ D\)
\((2, 4)\ \text{must satisfy}\)
\(\therefore\ \text{NOT}\ A\ \text{as}\ 2\times 2+3\neq\ 5\)
\(\Rightarrow B\)
What is the equation of the line \(l\)?
\(C\)
\(l\ \ \text{passes through (0, 5) and (1, 0)}\)
\(\text{Gradient}\) | \(=\dfrac{y_2-y_1}{x_2-x_1}\) |
\(=\dfrac{5-0}{0-1}\) | |
\(=-5\) |
\(y\ \text{-intercept}= 5\)
\(\therefore\ y=-5x+5\)
\(\Rightarrow C\)
The equation of the line drawn in the diagram below is:
\(B\)
\(y\text{-intercept}=+8\)
\(\text{Gradient}\) | \(=\dfrac{\text{rise}}{\text{run}}\) |
\(=-\dfrac{8}{5}\) |
\(\therefore\ \text{Equation is}:\ y=-\dfrac{8}{5}x+8\)
\(\Rightarrow B\)
The diagram shows the graph of a line.
What is the equation of this line? (2 marks)
\(y=\dfrac{1}{6}x+1\)
\(y\text{-intercept}=1\)
\(\text{Gradient}\) | \(=\dfrac{\text{rise}}{\text{run}}\) |
\(=\dfrac{1}{6}\) |
\(\therefore\ \text{Equation:}\ \ y=\dfrac{1}{6}x+1\)
What is the equation for the line shown?
\(D\)
\(\text{Line cuts}\ \ y\text{-axis at 1}\)
\(\text{Gradient}=\dfrac{\text{rise}}{\text{run}}=\dfrac{3}{4}\)
\(\therefore\ y=\dfrac{3}{4}x+1\)
\(\Rightarrow D\)
Which of these equations represents the line in the graph?
\(C\)
\(\text{Graph passes through }(0, 9)\text{ and} (4, 0)\)
\(\text{Gradient}\) | \(=\dfrac{y_2-y_1}{x_2-x_1}\) | |
\(=\dfrac{9-0}{0-4}\) | ||
\(=-\dfrac{9}{4}\) |
\(\therefore\ \text{Equation is:}\ \ y=9-\dfrac{9}{4}x\)
\(\Rightarrow C\)
Which of the following could be the graph of \(y=-2-2x\)?
\(B\)
\(\text{By elimination:}\)
\(y\text{-intercept} =-2\ \rightarrow\ \text{Eliminate}\ A \text{ and}\ D\)
\(\text{Gradient is negative}\ \rightarrow\ \text{Eliminate}\ C\)
\(\Rightarrow B\)