Answer:
adult cost £7, child cost £2
Step-by-step explanation:
let a represent an adult and c a child , then
2a + 3c = 20 → (1)
a + 4c = 15 → (2)
Multiplying (2) by - 2 and adding to (1) will eliminate a
- 2a - 8c = - 30 → (3)
Add (1) and (3) term by term to eliminate a, that is
- 5c = - 10 ( divide both sides by - 5 )
c = 2
Substitute c = 2 into either of the 2 equations and evaluate for a
Substituting into (2)
a + 4(2) = 15
a + 8 = 15 ( subtract 8 from both sides )
a = 7
The cost of an adult ticket is £7 and a child ticket is £2
Answer: " 4x + 2xy - 7pq " .
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Explanation:
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Given: " <span>4x - 7xy + 9xy - 7pq " ; Simplify the expression;
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Combine the "like terms:
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-7xy + 9xy = 2xy ;
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Now, rerewrite the expression, substituting the "-7xy + 9xy"; with " + 2xy" ;
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</span>→ " 4x + 2xy - 7pq " .
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</span>
Let x = amount of 45% antifreezeLet y = amount of 70% antifreeze EQUATION 1: x + y = 150 (total of 150 gallons mixed) EQUATION 2: .45x + .75y = .55(x + y) Simplify and solve the system of equations Multiply second equation by 100 on both sides to remove the decimals 45x + 75y = 55(x + y) Combine like terms 45x + 75y = 55x + 55y 45x - 55x + 75y - 55y = 0 -10x + 20y = 0 Now we have the following system of equations: x + y = 150 -10x + 20y = 0 Multiply the first equation by -10 to get opposite coefficients for x; add the equations to eliminate x 10x + 10y = 1500 -10x + 20y = 0 ------------------------------ 30y = 1500 Solve for y 30y = 1500 y = 50 Since the total mixed gallons is 150, x = 150 - 50 = 100 So we need 100 gallons of the 45% antifreeze and 50 gallons of the 70% antifreeze
Answer:
Step-by-step explanation:
A question on a math quiz asks, "What is 175% of 72?" Petra calculates 12.6 as the answer. Is this a reasonable answer? Explain
Answer:
J = 15
Step-by-step explanation:
In order to find what the variable equals, you need to put it alone on one side of the equation. So to get rid of the 5, you have to do the opposite of division, which is multiplication. You multiply 5 and 3 to get 15. This will look like:
15 = J
Usually, there is something left to do on the number side, but in this case, there is nothing and you found your answer!
