andrew says that in 15 years, the building he lives in will be twice as old as it was 7 years ago. how old is the building that andrew lives in?
Answers
Answer:
29 years old
Step-by-step explanation:
let the building current age be x
then in 15 years time the age of the building is x + 15
7 years ago the buildings age is x - 7 and twice as old is 2(x - 7)
equating the expressions
2(x - 7) = x + 15 ← distribute parenthesis on left side
2x - 14 = x + 15 ( subtract x from both sides )
x - 14 = 15 ( add 14 to both sides )
x = 29
the age of the building is 29 years
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Which equation is true for x = –6 and x = 2?2x2 – 16x + 12 = 0 2x2 + 8x – 24 = 0 3x2 – 4x – 12 = 0 3x2 + 12x + 36 = 0
Answers
36*100=45x
3600=45x /:45
x=80
Her goal was 80 bags of peanuts
Answers
Answer:
2√3
Step-by-step explanation:
5√3 - √27
= 5√3 - √9√3
= 5√3 - 3√3
=2√3
6x+y=2
-x-y=-3
System B:
2x-3y=-10
-x-y=-3
Which of the following statements is correct about the two system equations?
A) The value of x for System B will be 4 less than the value of x for System A because the coefficient of x in the first equation of System B is 4 less than the coefficient of x in the first equation of System A.
B) They will have the same solution because the first equations of both the systems have the same graph.
C) They will have the same solution because the first equation of System B is obtained by adding the first equation of System A to 4 times the second equation of System A.
D) The value of x for System A will be equal to the value of y for System B because the first equation of System B is obtained by adding -4 to the first equation of System A and the second equations are identical.
Answers
6x + y = 2
-x - y = -3
System B:
2x - 3y = -10
-x-y = -3
Solve:
System A:
6x + y = 2
y = 2 - 6x
-x - (2-6x) = -3
-x - 2 + 6x = -3
5x = -3 + 2
5x = -1
x = -1/5
y = 2 - 6(-1/5)
y = 2 + 6/5
y = 2 + 1.2
y = 3.2 System A: x = -1/5 or -0.2 ; y = 3 1/5 or 3.2
System B:
2x - 3y = -10
2x = -10 + 3y
x = -5 + 1.5y
-x - y = -3
-(-5 + 1.5y) -y = -3
5 - 1.5y - y = -3
-2.5y = -3 - 5
-2.5y = -8
y = 3.2
x = -5 + 1.5(3.2)
x = -5 + 4.8
x = -0.2 System B: x = -0.2 ; y = 3.2
B) They will have the same solution because the first equations of both the systems have the same graph.
Answer: I just took the test and got it wrong when I put B, the correct answer is C.
Step-by-step explanation:
Answers
Answer:
X = 5
Step-by-step explanation:
3x + 4 = 19
-4. -4
3x = 15
divide both sides by 3 to solve for x
x = 5
3m + 4c +7d = 5.45
Answers
One solution is c = -1, d = 0, m =3.15; and so on .........
Answer:
i dont know but good luck
Step-by-step explanation:
sorry tried my best
Answers
So you can exclude 540 as an answer
180 is a straight line in a pentagon there is no straight line angle so exclude that
72 and 108 both feasible id say