Answer:
B. 1,900
Step-by-step explanation:
Answer:
The “E” indicates an arc welding electrode. The first two digits of a 4-digit number and the first three digits of a 5-digit number stand for tensile strength. So, “1” stands for an all position electrode, “2” for a flat and horizontal electrode, and “4” for a flat, horizontal, vertical down and overhead electrode
Answer:
5/4
Step-by-step explanation:
2(8x-3)-4(3x-5)=19
16x-6-12x+20=19
16x-12x-6+20=19
4x+14=19
4x=19-14
4x=5
x=5/4
First, you need to rewrite the expression into binomial form, so you are working with two terms (as you world with a quadratic):
(x²)²-3(x²)-4=0
Now, you can place the x²s into brackets as the coefficient is now 1:
(x² )(x² )
Next, find out two numbers that add together to give you -3 and multiply to give -4 (these are the leftover integers after removing the x²s). These two numbers are -4 and 1.
Place the -4 and 1 into the brackets:
(x²-4)(x²+1)=0
Notice that the x²-4 is a difference of two squares, so can be further factorised into (x+2)(x-2)
This leaves you with a final factorisation of:
(x+2)(x-2)(x²+1)=0
Now we handle each bracket individually to obtain our four solutions for x:
x+2=0
x=-2
x-2=0
x=2
x²+1=0
x²=1
x=<span>±1</span>
2hr = 2km
1hr = 2km ÷ 2hr
= 1km
So, Tom's average speed is 1km/hr
