The explicit formula for arithmetic sequence is:
an=a+(n-1)d
where:
a=first term
d=common difference
given:
a3=22
a(17)=-20
substituting this in our equation we get:
22=a+(3-1)d
22=a+2d
a=22-2d........i
also:
-20=a+(17-1)d
-20=a+16d.....ii
but substituting i in ii we get:
-20=22-2d+16d
-20-22=14d
-42=14d
d=-3
but:
a=22-2d
a=22-2(-3)
a=28
thus the formula will be:
an=28-3(n-1)
thus the first term will be 28
the 2nd term will be:
a2=28-3(2-1)
a2=25
the 3rd term will be:
a3=28-3(3-1)
a3=28-6
a3=22
a4=28-3(4-1)
a4=28-9
a4=15
a5=28-3(5-1)
a5=28-3(4)
a5=28-12
a5=15
<span><em />
3x+y=5</span>
<span /><span>2x-2y=22 ...............2(x-y)=22 ⇒ x-y=11</span><span><em /></span>
<span><em>3x+y=5</em></span>
<span /><span><em><u>x-y=11 </u> </em>(+)</span>
<span />3x+x+y-y=11+5
<span>4x=16 /:4</span>
<span /><em>x=4</em>
x-y=11
4-y=11
-y=7 /*(-1)
<em>y=-7</em>
<span><em></em></span>
Answer:
A line of cars will be about 9650000 feet
Step-by-step explanation:
Simple:
Hope this Helps!
Stay Safe!
Answer:
Step-by-step explanation:
1. 2x + y
2. 48 + 60 = 108
3. 840 - 210 = 630