1. (3x- $2^{4}$ ). $7^{3}$ = 2. $7^{4}$
2. 43+ (9- 21)= 317- (x+ 317)
3. (x+ 1)+ (x+ 2)+ (x+ 3)+…..+ (x+ 100)= 7450
1. (3x- $2^{4}$ ). $7^{3}$ = 2. $7^{4}$ 2. 43+ (9- 21)= 317- (x+ 317) 3. (x+ 1)+ (x+ 2)+ (x+ 3)+…..+ (x+ 100)= 7450
By Emery
By Emery
1. (3x- $2^{4}$ ). $7^{3}$ = 2. $7^{4}$
2. 43+ (9- 21)= 317- (x+ 317)
3. (x+ 1)+ (x+ 2)+ (x+ 3)+…..+ (x+ 100)= 7450
Đáp án:
Giải thích các bước giải:
1, 3x – 2^4 = 7^4 : 7^3 . 2
=> 3x – 16 = 14
=> 3x = 30
=> x = 10
2, 43 – 12 = 317 – x – 317
=> 31 = -x
=> x = -31
3. ( x+x+…+x)( 100 số x) + (1+2+3+…+100) = 7450
=> 100x + 5050 = 7450
=> 100x = 2400
=> x = 24
`(3x- 2^4 ). 7^3 = 2. 7^4`
`=> 3x-2^4=2.7=14`
`=> 3x=14+16=30`
`=>x=10`
`2. 43+ (9- 21)= 317- (x+ 317)`
`=> 43-12=-x`
`=>x=12-43=-31`
`3. (x+ 1)+ (x+ 2)+ (x+ 3)+…..+ (x+ 100)= 7450`
`=(x+1+x+100).50=7450`
`=> 2x+101=149`
`=>x=\frac{149-101}{2}`
`=>x=24`