Step-by-step explanation:
If x is the mass of 30% copper alloy, and y is the mass of 65% copper alloy, then:
x + y = 80
0.30x + 0.65y = 0.51(80)
Solving the system of equations using substitution:
0.30x + 0.65(80 − x) = 0.51(80)
0.30x + 52 − 0.65x = 40.8
11.2 = 0.35x
x = 32
y = 80 − x
y = 48
The metalworker needs 32 kg of 30% copper alloy and 48 kg of 65% copper alloy.
Answer:
x^2 / 4pi
Step-by-step explanation:
The area of a circle is (pi x r)^2
The circumference of a circle is 2pi x r
The find the radius, you need to divide x by 2pi, so x / 2pi
Then just plug it in as the radius:
(pi x (x / 2pi))^2 = x^2 / 4pi
Answer:
Step-by-step explanation:
Call T the top
call G the bottom
T G B is a right triangle
37 at B, 90 at G, thus 53 at BTG
TGA is a right triangle
25 at A, 90 at G, thus 65 at ATG
thus 122 at ABT
law of sines:
sin 25 / BT = sin 12/ 57
so BT = 156 meters (first answer)
now angle ABT = 180 - 12 - 25
= 143
so
sin 143 /AT = sin12/57
AT = 164 meters, second answer
Answer:
C. 2 + (-3)
Step-by-step explanation:
-2.69 can be rounded to -3 and 1 can be rounded to 2
Answer:
x=2
Step-by-step explanation:
4x−7(2−x)=3x+2
4x+(−7)(2)+(−7)(−x)=3x+2(Distribute)
4x+−14+7x=3x+2
(4x+7x)+(−14)=3x+2(Combine Like Terms)
11x+−14=3x+2
11x−14=3x+2
Step 2: Subtract 3x from both sides.
11x−14−3x=3x+2−3x
8x−14=2
Step 3: Add 14 to both sides.
8x−14+14=2+14
8x=16
Step 4: Divide both sides by 8.
x=2