I think it’s b! i hope that helps!
Find the soluiton
2x+2y=16
3x-y=4
x+y=8
<u>3x-y=4+</u>
4x=12
x=3
3(3)-y=4
9-y=4
y=5
(3,5)
test them to see if get true statment
obviously the first equatons of 1,2,4 work
1 doesn't work
2, works
4. doesn't work
2 is the same as the first except both euations are just doubled
answer is 2
Answer:
sally ride I guess
Step-by-step explanation:
Its b and a hope this helps
800 different sets of digits
Since the first digit is a factor of 20, the factors of 20 are 1,2,4,5,10,20. We only need the single digit factors which are 1,2,4 and 5. These 4 numbers can be permuted in 1 way for the first digit, so we have ⁴P₁.
For the second digit, we have 10 digits permuted in 1 way, ¹⁰P₁ and also for the third digit, we have 10 digits permuted in 1 way, ¹⁰P₁ and for the last digit, which is divisible by 5, it is either a 0 or 5, so we have two digits permuted in 1 way, ²P₁.
So, the number of different 4 digit number that Zara'2 4-digit PIN code could be is ⁴P₁ × ¹⁰P₁ × ¹⁰P₁ × ²P₁ = 4 × 10 × 10 × 2 = 800 different sets of digits