Answer:
1
Step-by-step explanation:
Answer:
Step-by-step explanation:
- (x+y-z)²= 4xy
- (x+y-z)²- 4xy = 0
- (x+y-z)²-(2√x√y)² = 0
- (x+y-z-2√x√y)(x+y-z+2√x√y) =0
- [(√x-√y)²-z]*[(√x+√y)²-z]=0
- (√x-√y)²-z = 0 or (√x+√y)²-z = 0
We have : z^(1/2)= x^(1/2)+y^(1/2) ⇒ √z = √x + √y ⇒ z = (√x + √y)²
so (x+y-z)²= 4xy
So 4's facts
we know that 4 times 2=8 and the associative property of multiplication says
a(bc)=(ab)c
so 7(8) (means 7 times 8) means 7((4)(2)) and associative say we can group them and say (7)(4)(2) so (4)((7)(2)) or 4(14) and 4 times 14=56
7 times 8=56
Notice it is +/-4 times standard deviation (0.65-0.04 = 0.61, 0.69-0.04=0.65)
That's almost everything. So (D) is the answer.
<span>99.993666</span>%
Answer:
41 and 77
Step-by-step explanation:
x: his age the first time he went to space
y: his age the second time he went to space
the second time he went to space he was 5 years younger than twice the age when he went his first time, then:
y = 2x - 5
the sum of both ages is 118, then:
x + y = 118
If you replace y = 2x - 5 in x + y =118:
x + 2x - 5 = 118
3x = 123
x = 41
replacing x:
41 + y = 118
y = 118 - 41
y = 77
so when he was 77, he was 5 years younger than twice 41 ( 41*2 = 82 => 82 - 5 =77)
