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Leo knows that the slope of a line is -4 and Ine line passes through the point (-7, 18). Without doing any calculations, can Leo easily write an equotion for the line in slope-intercept form? Why or why not?​

User Otocon
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Leo can write the equation of the line in slope-intercept form as y = -4x - 10.

Even without doing any calculations, Leo can easily write an equation for the line in slope-intercept form by knowing the slope and using a point on the line to determine the y-intercept.

Leo can easily write an equation for the line in slope-intercept form without doing any calculations. The slope-intercept form of a linear equation is y = mx + b, where m represents the slope and b represents the y-intercept.

In this case, Leo knows that the slope of the line is -4. Therefore, he can write the equation as y = -4x + b. However, he still needs to determine the value of b, which represents the y-intercept.

To find the y-intercept, Leo can use the fact that the line passes through the point (-7, 18). Since the point lies on the line, its x and y coordinates must satisfy the equation. So Leo can substitute the x and y values of the point into the equation to find b.

Using the x and y values from the point (-7, 18), Leo can write the equation as 18 = -4(-7) + b. By simplifying this equation, Leo can solve for b:

18 = 28 + b

18 - 28 = b

-10 = b

Therefore, Leo can write the equation of the line in slope-intercept form as y = -4x - 10.

In summary, even without doing any calculations, Leo can easily write an equation for the line in slope-intercept form by knowing the slope and using a point on the line to determine the y-intercept.

User Sharan
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