Top equation, minus 10 both sides to get
3x-2y=-10
bottom equation, minus 4x both sides
5y-4x=8
-4x+5y=8
now elimiate y's
multiply top equation by 5 and bottom equaiton by 2 and add them together
15x-10y=-50
<u>-8x+10y=16 +</u>
7x+0y=-34
7x=-34
divide both sides by 7
x=-34/7
sub back
3x-2y=-10
3(-34/7)-2y=-10
(-102/7)-2y=-10
add (102/7) to both sides
-2y=-10+(102/7)
-2y=(-70/7)+(102/7)
-2y=32/7
divide both sides by -2, or times both sides by -1/2
y=-32/14
y=-16/7
(x,y)
(-34/7,-16/7)
Answer:
25
Step-by-step explanation:
Answer:
4920
7084800
2585952000
Step-by-step explanation:
82 chirps = 1 minute
We have 60 minutes in one hour, so 82 x 60 =4920 chirps in one hour
In 24 hours we have 60x24 = 1440 minutes and in one minutes we have 4920 chirps,
Therefore 4920 x 1440 mins =7084800 chirps in one day .
There are 365 days in a year and in one day the cricket chirps 7084800, so 365 days x 7084800 = 258595200 chirps in a year
Let: eq 1:2x+5y=-55
eq 2:y=3x+6
by substituting eq 2 in eq 1 we get,
2x+5(3x+6)=-55
2x+15x+30+55=0
17x + 85=0
x=-85/17
x=-5
By substituting x value in eq 2,
we have,
y=3(-5)+6=-15+6=-9
