An arithmetic sequence is defined as follows:
2 answers:
Answer:
-448
Step-by-step explanation:
The sum of 28 terms of the arithmetic sequence with first term 92 and common difference -8 can be found using the formula for the sum of an arithmetic series.
Sn = (2a1 +d(n -1))(n/2) . . . . sum of n terms with first term a1, difference d
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<h3>series sum</h3>Using the above formula with a1=92, d=-8, and n=28, the sum is ...
S28 = (2·92 -8(28 -1))/(28/2) = (184 -216)(14) = -448
The sum of the first 28 terms of the sequence is -448.
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We know that
the equation of the line in <span>slope-intercept form--------------> y=mx+b
Part A)
</span>Passing through (2,5) and perpendicular to the line whose equation is -3x+y-6=0
<span>Step 1
find the slope m
</span><span>remember that if two lines are perpendicular mi*m2=-1
</span>-3x+y-6=0---------> y=3x+6-------------> m1=3
then
m2=-1/3
Step 2
find the value of b
point (2,5) m=-1/3
y=mx+b----------> 5=(-1/3)*2+b--------> b=5+(2/3)-----> b=17/3
Step 3
find the equation of the line in slope-intercept form
y=(-1/3)x+17/3
using a graph tool
see the attached figure
the answer part A) is y=(-1/3)x+17/3
Part B)
Passing through (2,5) and perpendicular to the line whose equation is -3x-6=7x; slope intercept form.
Step 1
-3x-6=7x---------> 10x=-6 -----> x=-6/10-----> x=-3/5 (parallel to the axis y)
equation of the line is a constant so its perpendicular will be another constant defined by the coordinate y of the point through which it passes parallel to the axis x
point (2,5) ----------> the coordinate y=5
therefore
the perpendicular line is y=5 (parallel to the axis x)
using a graph tool
see the attached figure
the answer part B) is y=5
the equation of the line in <span>slope-intercept form--------------> y=mx+b
Part A)
</span>Passing through (2,5) and perpendicular to the line whose equation is -3x+y-6=0
<span>Step 1
find the slope m
</span><span>remember that if two lines are perpendicular mi*m2=-1
</span>-3x+y-6=0---------> y=3x+6-------------> m1=3
then
m2=-1/3
Step 2
find the value of b
point (2,5) m=-1/3
y=mx+b----------> 5=(-1/3)*2+b--------> b=5+(2/3)-----> b=17/3
Step 3
find the equation of the line in slope-intercept form
y=(-1/3)x+17/3
using a graph tool
see the attached figure
the answer part A) is y=(-1/3)x+17/3
Part B)
Passing through (2,5) and perpendicular to the line whose equation is -3x-6=7x; slope intercept form.
Step 1
-3x-6=7x---------> 10x=-6 -----> x=-6/10-----> x=-3/5 (parallel to the axis y)
equation of the line is a constant so its perpendicular will be another constant defined by the coordinate y of the point through which it passes parallel to the axis x
point (2,5) ----------> the coordinate y=5
therefore
the perpendicular line is y=5 (parallel to the axis x)
using a graph tool
see the attached figure
the answer part B) is y=5