Here is one way to solve for x.
Step 1) 2x^2-7=9
Step 2) 2x^2-7+7=9+7
Step 3) 2x^2=16
Step 4) (2x^2)/2=16/2
Step 5) x^2=8
Step 6) sqrt(x^2)=sqrt(8)
Step 7) |x|=sqrt(8)
Step 8) x=sqrt(8) or x=-sqrt(8)
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Below are explanations/reasons to each of the steps above.
Step 1) Original equation
Step 2) Add 7 to both sides
Step 3) Combine like terms
Step 4) Divide both sides by 2
Step 5) Simplify
Step 6) Apply the square root to both sides. The notation "sqrt" is shorthand for "square root"
Step 7) Use the rule that sqrt(x^2) = |x| for all real numbers x
Step 8) Use the rule that if |x| = k then x = k or x = -k for some fixed number k.
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The two solutions are
x = sqrt(8) or x = -sqrt(8)
Answer: 175
Step-by-step explanation: total = x + 5y dollars and dollars = 300 so
x + 5y = 300 then since we know y = 200 we can substitute that
x + 5(200) = 300 then subtract x from 200
x + 5(200 - x) = 300 now solve for x
x + 5(200) + 5(-x) = 300 we know 5 times 200 is 1000
x + 1000 - 5x = 300 then subtract 5x - x = -4x
-4x + 1000 = 300 switch around 1000 and 300
-4x = 300 - 1000 subtract 300 - 1000 = -700
-4x = -700 multiply
x = -700/(-4) then finish up and solve
x = 175
hope this helps please mark brainliest if you can
Answer:
let x =the original price
then 116x/100=$39.32
116x=100×39.32
116x=3932
divide both sides by 116
116x/116=3932/116
x=33.89655
(2dp)
x=33.90
Answer:
vertex =
(
4 , 25
)
Step-by-step explanation:
given a parabola in standard form y
= a
x
2
+
b
x
+
c
x
;
a
≠
0
then the x-coordinate of the vertex is
X vertex=-b/2a
y=-x2+8x+9 with a=-1 b=8 c=9
X vertex= -8/-2=4
substitute the value on the equation
Y vertex = -(4)squared+8(4)+9=25
