Question
Question: How do you graph \(y=-2x+10\) ?...
How do you graph y=−2x+10 ?
Solution
In this question, we have to draw the graph of a given equation. The equation given to us consists of two variables, will we draw a two-dimensional graph. For drawing the graph, we have to use the substitution method to get the values of x and y, so that we can plot a graph. First, we put different values of x in the equation and solve for y. Similarly, we put different values of y in the equation and solve for x. Then, we plot those coordinates in the two-dimensional graph and join all the points to get a required curve or a straight line.
Complete step by step answer:
According to the question, it is given that equation is y=−2x+10 --------- (1)
We will apply the substitution method in the above equation, that is
Let x=0 in equation (1), we get
⇒y=−2(0)+10⇒y=0+10
Therefore, we get
⇒y=10
Thus, coordinate will become A(x,y)=A(0,10)
Let y=0 in equation (1), we get
⇒0=−2x+10
Now, subtract 10 on both sides of the above equation, we get
⇒0−10=−2x+10−10
As we know, the same terms with different signs cancel out each other, we get
⇒−10=−2x
Now, divide 2 on both sides of the equation, we get
⇒2−10=2−2x⇒−5=−x
Now, we will multiply (-1) on both sides in the above equation, we get
⇒5=x
Thus, coordinate is B(x,y)=B(5,0)
Let x=1 in equation (1), we get
⇒y=−2(1)+10⇒y=−2+10
Therefore, we get
⇒y=8
Thus, coordinate is C(x,y)=C(1,8)
Let y=1 in equation (1), we get
⇒1=−2x+10
Now, subtract 10 on both sides in the above equation, we get
⇒1−10=−2x+10−10
As we know, the same terms with different signs cancel out each other, we get
⇒−9=−2x
Now, divide 2 on both sides of the above equation, we get
⇒2−9=2−2x⇒−4.5=−x
Now, multiply (-1) on both sides of the equation, we get
⇒−4.5.(−1)=−x.(−1)
Therefore we get
⇒4.5=x
Thus, coordinate is D(x,y)=D(4.5,1)
After finding these coordinates A(0,10), B(5,0), C(1,8), and D(4.5,1), we will plot these points on the graph, that is
After plotting these points, join these points to get a curve of equation y=−2x+10 .
Therefore, for the equation y=−2x+10 , we have plotted the graph using different coordinates.
Note: Do all the calculations carefully to avoid calculation mistakes. For plotting the graph, atleast find 4 coordinates to get a perfect curve or a straight line. Always mention the points on the graph.