Answer:
Therefore the required result is 9x-2y =0.
Step-by-step explanation:
Given equation are
x-3y =6.....(1)
-8x-y=6 .....(2)
Subtracting equation (2) from (1)
x - 3y = 6
-8x - y= 6
+ + - [ The sign of equation (2) will be change in case of
_________ subtraction and in case of plus the signs remains same ]
(x+8x)-3y+y=6-6 [ adding the like terms]
⇒9x-2y =0
Therefore the required result is 9x-2y =0.
Answer:
x=-2
Step-by-step explanation:
add 5x , then subtract 45, then divide by 15
$750 / $30 = 25 maths teaching kids
$350 / $25 = 14 maths starter kits
if you wanted to see if it was right, you would just do 14*25 and you would get $350
hope I helped!!
Answer:
Sum of the first 15 terms = -405
Step-by-step explanation:
a + 3d = -15 (1)
a + 8d = -30 (2)
Where,
a = first term
d = common difference
n = number of terms
Subtract (1) from (1)
8d - 3d = -30 - (-15)
5d = -30 + 15
5d = -15
d = -15/5
= -3
d = -3
Substitute d = -3 into (1)
a + 3d = -15
a + 3(-3) = -15
a - 9 = -15
a = -15 + 9
a = -6
Sum of the first 15 terms
S = n/2[2a + (n − 1) × d]
= 15/2 {2×-6 + (15-1)-3}
= 7.5{-12 + (14)-3}
= 7.5{ -12 - 42}
= 7.5{-54}
= -405
Sum of the first 15 terms = -405