What was Miguel's mistake if any?
2 answers:
You might be interested in
An equation of the form ax+by+c=0, where x, y are variable, and a, b, c are numbers, is called a "linear equation"
the reason we call it linear, is that all solutions (x, y) to this equation, when plotted in the x-y axis, form a line.
To draw this line, 2 points are enough, that is 2 solutions (x, y) of the equation.
-------------------------------------------------------------------------------------------------
-2x+5y-10=0 is a linear equation (a=-2, b=5, c=-10)
to find 2 solutions, we set x or y any value we want, and solve for the other
for example:
let x=0,
then
-2x+5y-10=0 becomes 5y-10=0, so y=2
this gives us the solution (0, 2)
another example; set y=0
then -2x+5y-10=0 becomes -2x-10=0; -2x=10 so x=-5
thus another solution is (-5, 0)
Draw these 2 points, and join them with a line, as shown in the figure.
the reason we call it linear, is that all solutions (x, y) to this equation, when plotted in the x-y axis, form a line.
To draw this line, 2 points are enough, that is 2 solutions (x, y) of the equation.
-------------------------------------------------------------------------------------------------
-2x+5y-10=0 is a linear equation (a=-2, b=5, c=-10)
to find 2 solutions, we set x or y any value we want, and solve for the other
for example:
let x=0,
then
-2x+5y-10=0 becomes 5y-10=0, so y=2
this gives us the solution (0, 2)
another example; set y=0
then -2x+5y-10=0 becomes -2x-10=0; -2x=10 so x=-5
thus another solution is (-5, 0)
Draw these 2 points, and join them with a line, as shown in the figure.
Given the next quadratic function:
to sketch its graph, first, we need to find its vertex. The x-coordinate of the vertex is found as follows:
where <em>a</em> and <em>b</em> are the first two coefficients of the quadratic function. Substituting with a = 2 and b = 3, we get:
The y-coordinate of the vertex is found by substituting the x-coordinate in the quadratic function, as follows:
The factorization indicates that the curve crosses the x-axis at the points (-2, 0) and (1/2, 0). We also know that the curve crosses the y-axis at (0,-2). Connecting these points and the vertex (-0.75, -3.125) with a U-shaped curve, we get:
