What you want to do is cross multiply so you get 5(x+4)=7(3x+28) then you distrubute the 5 and then you distribute the 5 and the 7 to the number in the parentheses 5x+20=21x+196
subtract 5x on both sides to get 20=16x+196 then you subtract 196 on both sides to get -176=16x last what you want to do is divide 16 on both sides to get x=-11
Answer:
7.236
Step-by-step explanation:
Let's assume that the original length of the piece of board is L.
Now you cut two pieces that are 3.4 ft long, so the remaining piece of board is:
L - 3.4ft - 3.4ft = L - 6.8ft long.
Now we know that the remaining must be 2.35 times longer than the pieces of 3.4 ft, then we have the equation:
( L - 6.8ft) = 2.35×3.4ft
solving that for L we get:
L = 14.79ft
Rounding to the nearest tenth, we get:
L = 14.8ft
You should buy a piece of board that is 14.8 feet long.
If you want to learn more, you can read:
brainly.com/question/22293035
We need to find 30% of 20 gallons.
1) We can write a proportion
20 gallons ---- 100%
x gallons --------30%
x = 20*30/100 = 6 gallons
2) Or we can write 30% as decimal.
30% = 30/100 = 0.3
0.3 of 20 = 0.3*20 =6 gallons
Answer 6 gallons are used efficiently.
Answer:
f(x) = -7x² - x + 2
Step-by-step explanation:
Quadratic functions are set up in the form ax² + bx + c. f(x) = 0x² + 3x -3 is also set up in this format but 0x² would simplify to 0 which means the equation is actually f(x) = 3x-3 and does not fit in the quadratic function format. The other equations are also not set up in ax² + bx + c.
