Answer:
A. m^2+7m+10=0
Step-by-step explanation:
This is a problem in pattern matching, and in substituting a variable for a pattern.
(x^2+3)^2 +7x^2 +21 = -10 . . . . . . given
(x^2 +3)^2 +7(x^2 +3) = -10 . . . . . factor the last two terms
m^2 +7m = -10 . . . . . . . . . . . . subsitute m for x^2 +3
m^2 +7m +10 = 0 . . . . . . . . add 10 to both sides; matches A
Answer:
x=5.6
y=-5.6
Step-by-step explanation:
3x - 5y = 14 Equation 1
– 2x + 2y = 0 Equation 2
Simultaneous equation can be solved either through elimination method or substitution method. But we use elimination method for this question
Multiply equation 1 by -2 (the coefficient of x in equation 2) and multiply equation 2 with 3 (the coefficient of x in equation 1), so that x will have the same coefficient in the new equations, and easy to eliminate
-2(3x - 5y = 14)
-6x+10y=-28 Equation 3
3(– 2x + 2y = 0)
-6x+6y=0 Equation 4
Subtract equation 4 from 3 to eliminate x
-6x+10y=-28
-6x+6y=0
-6x-(-6x)=-6x+6x=0
10y-6y=5y
-28-0=-28
5y=-28
y=-28/5
y=-5.6
Substitute for y in equation 2
– 2x + 2y = 0
– 2x + 2(-5.6) = 0
-2x-11.2=0
-2x=11.2
x=-11.2/2
x=5.6
Answer: Your answer is 17/33! Hope this helps. If you need anymore help let me know!
Answer:
$10 coins: 21
$20 coins: 24
Step-by-step explanation:
heyy me again
So we can create 2 equations where
x = number of $10 coins
y = number of $20 coins:
x + y = 45
10x + 20y = 690
we can move equation 1 around so that we can get a value of x
x = 45 - y
now we can substitute x into the second equation
10(45 - y) + 20y = 690
450 - 10y + 20y = 690
10y = 240
y = 24
Now plug in y back into the first equation
x = 45 - y
x = 45 - 24
x = 21
