Answer:
144
Step-by-step explanation:
12 times 12
Answer:
Step-by-step explanation:
If you call "5x-2x^2+1" an "equation," then you must equate 5x-2x^2+1 to 0:
5x-2x^2+1 = 0
This is a quadratic equation. Rearranging the terms in descending order by powers of x, we get:
-2x^2 + 5x + 1 = 0. Here the coefficients are a = -2, b = 5 and c = 1.
Use the quadratic formula to solve for x:
First find the discriminant, b^2 - 4ac: 25 - 4(-2)(1) = 25 + 8 = 33
Because the discriminant is positive, the roots of this quadratic are real and unequal.
-b ± √(discriminant)
Applying the quadratic formula x = --------------------------------
2a
we get:
-5 ± √33 -5 + √33
x = ----------------- = --------------------- and
2(-2) -4
-5 - √33
---------------
-4
Note that fiona cannot sell decimal number of cupcakes or muffins. That's why the options A and D are false.
Consider all remaining options:
B. 40 cupcakes and 80 muffins will cost $(40·3+80·2)=$(120+160)=$280, but Fiona Follies sold at least $300 worth of cupcakes and muffins. Thus, this option is false.
C. 60 cupcakes and 70 muffins will cost $(60·3+70·2)=$(180+140)=$320. Now consider expenses. $(60·0.75+70·0.5)=$(45+35)=$80. This option is true.
E. 80 cupcakes and 80 muffins will cost $(80·3+80·2)=$(240+160)=$400. Now consider expenses. $(80·0.75+80·0.5)=$(60+40)=$100 (exactly $100). This option is true.
Answer: correct options are C and E.
-2x+4y=4 Equation 1
x-2y=6 Equation 2
Solving by substitution method.
Isolate x from equation 2.
x=2y+6
Substitute value of x in equation 1
-2(2y+6)+4y=4
-4y-12+4y=4
-12=4
-16=0
Which is false.
Answer: No solution
Answer:
320km/h
Step-by-step explanation:
You simply times 80 km by 4hr to get 320 km/h