First we will find the 11th term
an = a1 + (n-1) * d
a11 = 12 + (11 - 1) * 5
a11 = 12 + 10 * 5
a11 = 12 + 50
a11 = 62
now we use the sum formula...
Sn = (n (a1 + an)) / 2
S11 = (11 (12 + 62)) / 2
S11 = (11 (74)) / 2
S11 = 814/2
S11 = 407
Answer is: x=3
Add the two equations together to eliminate y from the system.
Then divide each term by 5 and simplify.
Simplify both sides of the equation
-25(x-4)=-55(x-10)
(-25)(x) + (-25)(-4)=(-55)(x) + (-55) (-10)
Distribute
-25x+100=-55x+550
Add 55x to both sides
-25x+100+55x=-55x+550+55x
30x+100-100=550-100
subtract 100 from both sides
30x+100-100=550-100
30x=450
divide both sides by 30
30x/30=450/30
x= 15
The value of x is 15
I hope that's help you my friend !
They’ve already earned $105 so they need $45 more to reach their goal
Answer:
S= 5/2
Step-by-step explanation:
