To solve this problem, we need to set-up algebraic expression. First, use variables to represent the number of beads.
Let: x = number of Xavier's beads
y = number of Y<span>aozhou's beads
z = number of Zara's beads
</span>It is important to note that since we have three unknowns, we should also have three independent equations. <span>Based on the given statements, we have the following three equations:
(1) x + y = 438
(2) x + z = 204
(3) y = 3z
Substitute y in terms of z in equation (1). Then multiply equation (2) with -1.
x + 3z = 438
-(x + z = 204)
-------------------
2z = 234
z = 117
From equation (3),
y = 3(117) = 351
Using equation (1),
x = 438 - 351 = 87
Thus, Xavier had 87 beads.</span>
Answer:
C. The number of electrons in the valence shell
Explanation:
When the valence shells are complete, the atom is unreactive. However, when they are incomplete, they are chemically reactive.
Answer: (1.5 M) V1 = (3.40 M) (500mL)
(multiply 3.40M x 500mL) V1 = 1700 mL
1700 mL of the 1.5 M NaCl + 1200mL of water.
Explanation:
Answer:
the chemical element of atomic number 2, an inert gas which is the lightest member of the noble gas series.
Explanation:
Because it is very unreactive, helium is used to provide an inert protective atmosphere for making fibre optics and semiconductors, and for arc welding. Helium is also used to detect leaks, such as in car air-conditioning systems, and because it diffuses quickly it is used to inflate car airbags after impact.