Solve the porportions. First, cross multiply
7/(x - 4) = 42/12
(7/(x-4))(x-4)(12) = (42/12)(12)(x-4)
7(12) = 42(x-4)
Simplify. (remember to distribute the 42 to both x and -4
84 = 42x - 168
Isolate the x. First add 168 to both sides
84 (+168) = 42x - 168 (+168)
42x = 84 + 168
42x = 252
Finally, isolate the x by dividing 42 from both sides
42x/42 = 252/42
x = 252/42
x = 6
6 is your answer
hope this helps
The answer is b y=6 Use photonath if any more equations like this one
Answer:
15%
Step-by-step explanation:
Please refer to the attached image for explanations
Step-by-step explanation:
it's obviously the equation is equals to zero,
-12x + 16 = 0
-12x = -16
-12. 12
like terms cancel each other to remaining with x
thus,
x = 4/3
<h2>AND</h2>
4x - 12 = 0
4x = 12
4. 4
like terms cancel each other to remaining (make x subject of the formula) with x
thus,
x = 3
Answer:
again i didnt answer the question i just found someone who did
hope it helps :)
Step-by-step explanation:
Let +a+ = liters of pure acid needed
Let +b+ = liters of 10% solution needed
+.1b+ = liters of pure acid in 10% solution
-----------------------------------------
(1) +a+%2B+b+=+135+
(2) +%28+a+%2B.1b+%29+%2F+135+=+.2+
---------------------------
(2) +a+%2B+.1b+=+27+
(2) +10a+%2B+b+=+270+
------------------------
Subtract (1) from (2)
(2) +10a+%2B+b+=+270+
(1) +-a+-+b+=+-135+
----------------------
+9a+=+135+
+a+=+15+
and
(1) +a+%2B+b+=+135+
(1) +15+%2B+b+=+135+
(1) +b+=+120+
-------------------
15 liters of pure acid are needed
120 liters of 10% solution are needed
--------------
check:
(2) +%28+a+%2B.1b+%29+%2F+135+=+.2+
(2) +%28+15+%2B.1%2A120+%29+%2F+135+=+.2+
(2) +27%2F135+=+.2+
(2) +27+=+27+