Answer:
She should use 32.5 g of the sample that contains 14%
Step-by-step explanation:
Here, we want to know the number of grams of the sample that contains 14% copper that should be used
let the number of grams that contains 14% copper to be used be x
Then the number of grams of 22% will be 130-x
Thus, mathematically;
0.14(x) + 0.22(130-x) = 0.2(130)
0.14x + 28.6 - 0.22x = 26
0.22x - 0.14x = 28.6 - 26
0.08x = 2.6
x = 26/0.08
x = 32.5
Answer:
Multiply the second equation by -3 to get -3x - 9y = -30.
Step-by-step explanation:
When eliminating, you need to find a term with the negative of that term to combine so that they cancel each other out. An example would be 3x in the first equation and (-3x) in another equation so that when added, it becomes: 3x-3x = 0.
In the second equation, you see that there is already an x there and you just need to make it become (-3x). Thus, you multiply the entire second equation by -3 to make -3x. Once you have done that, you can combine the two equations and eliminate 3x from the first equation.
3x + 5y = 30
-3x - 9y = -30
3x + 5y -3x - 9y = 30 + (-30)
0 - 4y = 30 - 30
-4y = 0
<em>You can find y and then x later on from here. </em>
What are you asking cause I do not get it
Answer:
65 or 60
Step-by-step explanation:
I am not really positive about my answers so please take this into consideration.
Given:
∠JEK + ∠DFH = 90°
Find:
relationship, if any, of ∠JEK to angles CFL, HFG, LFE
Solution:
We note that ∠DFG = 90° = ∠DFH + ∠HFG, so ∠JEK ≅∠HFG.
We also note that ∠HFG and ∠CFL are vertical angles, so ∠JEK ≅∠CFL.
And ∠LFE and ∠DFH are vertical angles, so ∠JEK + ∠LFE = 90°.
Evaluating the choices, we find
A) false. The angles are not complementary, they are equal.
B) false. The angles are not equal, they are complementary.
C) false. The angles are not supplementary, they are equal.
D) TRUE. The angles are equal.
The appropriate choice is ...
D) ∠JEK ≅∠CFL
