The first one.
Find the equation of the line that goes through the points (4, –1) and (2, –5).
2 answers:
Answer:
y= 2x -9
Step-by-step explanation:
<u>Slope-intercept </u><u>form</u>
y= mx +c, where m is the slope and c is the y-intercept.
Slope
= 2
Substitute m= 2 into the equation:
y= 2x +c
To find the value of c, substitute a pair of coordinates.
When x= 4, y= -1,
-1= 2(4) +c
-1= 8 +c
c= -1 -8
c= -9
Thus, the equation of the line is y= 2x -9.
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For any quadratic equation ax² + bx + c = 0, the solution is
In the case of our equation 7x² - x = 7, first we need to subtract 7 from each side so that we have 0 on the right.
7x² - x - 7 = 0
Identify the values of a, b, and c.
a = 7, b = -1, and c = -7.
Plug these into our quadratic formula and solve.
There are two values for x: (1+√197)/14 and (1-√197)/14.
The approximate values for these are 1.073976 and -0.931119.