I should answere should be C
Answer:
56
Step-by-step explanation:
Complete question:
Z varies jointly with x and y , x=2 and y=2, z=7. Find z when x=4 and y=8 using joint variation . (I need the problem worked out step by step)
If z varies jointly with x, and y, this is expressed as;
z = kxy
If z=7 when x= 2, y= 2
7 = k(2)(2)
7 = 4k
k = 7/4
To get z when x= 4 and y = 8
z = kxy
z =7/4 (4)(8)
z = 7*8
z = 56
Hence the value of z is 56
3y=4x-27
y=4/3x-9
That’s how you do the equation
Principal = 109,000
Return - 9,920
Return = (principal x rate x time)/100
X = the amount invested at 12%
Then 102000- x = the amount invested at 8%
9920 = (x*12)/100 + (109000-x*8)100
x = 30,000
a) 30,000 is invested at 12%
79,000 is invested at 8%
b) The 12% investment is riskier so if all the money was in that account the investor could lose all his money.
