I hope this helps you
2x^2-4x+7=0 a=2 b=-4 c= 7
disctirminant =b^2-4ac
disctirminant =(-4)^2-4.2.7
disctirminant = 16-56= -40
x=-b+square root of disctirminant ÷2a
x=4+2square root of (-10)/4
x=2+square root of (-10)/2
x'=4 -2 square root of (-10)/4
x'=2 -square root of (-10)/2
Answer:
2/9
Step-by-step explanation:
y=6(3)^x
Let x =-3
y = 6 * 3^-3
Remember negative exponents move it from the numerator to the denominator
y = 6 *1/3^3
y = 6 * 1/27
y = 6/27
y = 2/9
Y=250+2x is the amount she spends
y=12x is the amount she makes
If the amount she spent = the amount she makes then she break even
250+2x=12x
250=12x-2x
250=10x
So x = 250/10=25 necklaces she needs to sell to break even
Answer is 25 necklaces
There are a couple of equations u can use
x = original price
15% off the original price of the purchase :
x - 0.15x
OR
if u get 15% off, then u are paying for 85%
0.85x