Answer:
Step-by-step explanation:
so basically you have to look for the opposite side of what they give you. then just plot it in
So use cancelation
multiply first equation by 2
2x+8y=10
times 2
4x+16y=20
now add
4x+16y=20
<u>-4x-9y=-13 +
</u>0x+7y=7
7y=7
divide by 7
y=1
subsittue
2x+8y=10
2x+8(1)=10
2x+8=10
subtract 8 from both sides
2x=2
divide by 2
x=1
x=1
y=1
<u />
Answer:
The answer is 20
Step-by-step explanation:
Reasoning it is correct because for questions like this the bottom numbers for each shape are 10 and 8 they are very close to each other on the number line there fore since the number is two off you subtract 2 and then two again since it is 2 off to get 21 the closest answer is 20
It is a little confusing but since it is two places off you subtract two twice
Answer:
See proof below
Step-by-step explanation:
Let
. If w=-z, then r=0 and r is real. Suppose that w≠-z, that is, r≠0.
Remember this useful identity: if x is a complex number then
where
is the conjugate of x.
Now, using the properties of the conjugate (the conjugate of the sum(product) of two numbers is the sum(product) of the conjugates):

=
Thus
. From this,
. A complex number is real if and only if it is equal to its conjugate, therefore r is real.