Let's let the weight of a large box be L, and the weight of a small box be S.
We know that 5 large boxes and 3 small boxes is 120kg, so:
5L + 3S = 120
We also know that 7 large boxes and 9 small boxes is 234kg, so:
7L + 9S = 234
You can multiply the first equation by 3 to get:
15L + 9S = 360
See how now both equations have 9S? We can now subtract one from the other:
(15L+9S) - (7L+9S) = 360-234
8L = 126
L = 15.75
Now sub this value back into an equation:
(5x15.75) + 3S = 120
3S = 41.25
S = 13.75
Double check these values
(7x15.75) + (9x13.75)
= 110.25 + 123.75
=234, which is consistent with above.
So a large box is 15.75kg, and a small box is 13.75kg.
Hope this helped
Answer:
Step-by-step explanation:
tan(30°) = 
cot(30°) = 
sin(60°) = 
Let's first write the equation given
x²+6x-13=0
They have told us to use "Completing the square" method.
So we need write x²+6x-13 as a whole square.
x²+6x-13=0
x²+(2*3*x)-9-4 = 0
x²+(2*3*x)-3²=4
Now we can write the LHS as:
(x - 3)²=2²
Hence,
x-3 can either be 2 or -2
Now,
x - 3=2
x=5
Or,
x - 3=-2
x=1
Therefore now we know that x can either be 1 or 5. So the correct answer is Option B.
║a+9║/7=5
you multiply 7 on both sides which cancel out 7.
now it ║a=9║=35
and now it would be a+9=35 and a+9=-35 then solve it.
35-9 and 9-(-35)= 26 and -44
hope this helped!
